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ScanUp -
A must-have app for online exams With the ban on Chinese apps, PM Modi initiated the ‘Make in India’ challenge last year, and five first-year IIT Delhi students took up this challenge and thus ScanUp was born!
Written by GOPIKA ARORA Designed by PINNINTI RENU SREE
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ith the ban on Chinese apps, PM Modi initiated the ‚Make in India‘ challenge last year, and here I present to you five first-year IIT Delhi students who took up this challenge and were recognized by the ministry of education of India. Archit Bubna, Rajdeep Singh Dhingra, Ritvik Gupta, Pranjal Aggarwal, and Deepanshu Rohilla are currently sophomores in the computer science and the mathematics and computing department at IIT Delhi. These enterprising students often found themselves discussing challenges and problems, and it was such a discussion that led them to come together and decide to work on an app that could replace the newly banned and popularly used Chinese ones. However, they couldn‘t participate in that particular competition due to time constraints but did end up creating ScanUp, an app to replace CamScanner at the time of work from home jobs and education.
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Source: ScanUp
They initially wanted to do something that didn’t exist before - convert videos to pdf; however, the first step was, of course, to be able to extract it from images - make a basic functioning app and build upon the already existing apps and then add on more features (which are currently in the works). This app’s working is pretty straight forward - you click and add images that go through an algorithm that processes and auto crops it without distortion (you can manually change this too), after which some filters can be applied before you get the final document within seconds. When asked a rather blunt question- Do you think your app is better than the existing apps?, Rajdeep started with a modest reply that he couldn‘t say for sure whether it was better since apps like CamScanner have existed for a long time and have huge teams working on it. But ScanUp does provide certain advantages over them- ScanUp is entirely offline, unlike some of the other apps which have components that work online. This is important because there is no threat of data breach, and complete privacy is guaranteed. This app is also free to use and without watermarks or advertisements. However, these are just bonus points, in the pure aspects as well, Dhingra declares that their app has much better detection quality and filters than the other Indian alternates that have popped up recently.
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This definitely isn’t the end of the story; the five have exciting new features up their sleeves that they’ll work on as soon as the IITD academics gives them space to breathe. These are- as described earlier, video to pdf convertor. It is often tiresome to click 20 pictures to create a pdf, and they look forward to working on something that would allow you to take a video of you flipping the pages and extract the pdf. They also plan to have a data backup option on the user’s personal account (the developers would not be privy to it) and a password protection option for certain important documents. They look forward to bettering their text-recognition option too, which is currently a crude form of what they hoped to make.
THE TEAM
Name : Ritvik
Name: Rajdeep & Archit
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Overall, it has been an exciting journey with great results, but their tale doesn’t end here. Download ScanUp and watch out for the exciting new features that the ‘best brains of the country’ have in store!
Name : Deepanshu
APPRECIATION FROM THE MINISTRY OF EDUCATION Source: Twitter
Name : Pranjal
As for the response, the app was warmly received and greatly appreciated by the IITD community. The director of the institute also shared it through his Facebook and LinkedIn accounts. However, the reach outside of IIT Delhi is not great yet; they plan to work more on marketing once they improve the USPs. However, the app was appreciated and shared through the Minister of Education’s social media pages, and that has undoubtedly helped boost the popularity of the app. Currently, there are around 20k downloads of the app at the moment. The journey has been difficult working remotely without professors or seniors’ guidance, but they hope that it will be easier when they’re back on campus and can work on it together. However, the development phase, they say, was quite exciting, and they learned a lot- working around 10hrs a day and sometimes scratching their heads over bugs (not the insects) that took as long as 2-3 days to resolve.
THE APP Source: ScanUp
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An ISRO Response Project:
Wireless Sensor for Landslide Prediction A team of undergraduates from IIT Madras have consistently been working on building industry-grade drones and providing aerial solutions that elevate efficiency and profitability for the industries. The race is on to build perfect drones that are easy enough to operate without any formal training.
Written by VARUN GANTA,NAREN LOGANATHAN Designed by NIDAMANURI CHANIKYA GUPTA
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r. Albert Sunny received his PhD and MSc degrees in Engineering from IISc (Indian Institute of Science), Bangalore. He is currently an Assistant Professor at IIT Palakkad’s Department of Computer Science and Engineering. Prior to this, he was a post-doctoral researcher at INRIA, France. His research interests and publications are largely focused on the analysis and modelling of wireless, social and transportation networks. Dr. Sudheesh T. K. did his PhD in Civil Engineering from University of Florida, USA. He has done an extensive amount of work in areas such as Geotechnical Engineering, Foundations, Slope Stabilization and Soil Structure Interactions. At present, he is an Assistant Professor at the Civil Engineering Department here at IIT Palakkad.
Landslides A landslide (also known as a landslip) refers to the movement of a large amount of rock, earth, or debris, down a sloped section of land. Landslides are mostly caused by rain, earthquakes, and less noticeable factors such as soil erosion. They are a frequent occurrence in hilly regions that experience heavy rainfall, such as northeast India. Human activities such as construction and mining are also known to exacerbate the risk of landslides. Landslides can be devastating – often claiming lives and damaging infrastructure. Landslides can also increase the risk of flooding when they occur near rivers and other water bodies.
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Being able to predict the chances of a landslide occurring in a particular area (ahead of time) is a valuable ability that could potentially save lives and mitigate damage. Hence, the need for a real-time monitoring system that can predict slope failure that is in the works at IIT Palakkad. Piloted by Dr. Albert Sunny and Dr. Sudheesh, this project not only aims to be robust, but also cost-effective, energy-efficient and easy to deploy.
A Zigbee Network Solution The team plans on achieving the objective of predicting landslides with the help of a solar powered Zigbee-based wireless sensor network. Zigbee is a wireless technology developed as an open global standard to address the unique needs of low-cost, low-power wireless IoT (Internet of Things) networks. The idea is to place wireless sensors in areas which are prone to landslides, so that physical quantities of interest such as pore water pressure (pressure of groundwater held in the soil), rainfall and soil movement can be monitored. These parameters are known to significantly impact the chances of a landslide occurring. Hence, these observations can be used to compute the probability of slope failure with the help of appropriate algorithms.
open-source technologies such as React, Node. js and MongoDB were used in building a full-stack solution (such an implementation is often called a ‘MERN’ stack). React was used in the front-end development process, and Node.js for the back-end. MongoDB was used as the database (to store sensor data).
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React.js -> an open-source JavaScript library focused on the development of user interfaces. Node.js -> an open-source JavaScript runtime environment that executes code outside a web browser. MongoDB -> a document database that stores the data in JSON-like (file format) documents.
Express.js, a minimal and flexible Node.js web application framework, was also used in the back-end development of the full-stack. Using Express.js allows for URL routing and handling requests/responses, making it perfect for accessing and updating data in the MongoDB database (on obtaining requests from React.js). The main objective of REST APIs is to enable a client to get desired data by pointing to a specific URL, with the URL acting as the request and the data obtained being the response.
One of the core objectives of this project is to use these sensors to relay valuable data in realtime to organisations such as NESAC (The North Eastern Space Applications Centre) so that they can assess the risk of a landslide occurring in a particular region at a particular instant. The implementation of a full-stack facilitates this.
Talking Tech : A Full Stack To take in, understand and view the information sent by various sensor nodes,
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INTERACTION AMONG VARIOUS COMPONENTS OF THE FULL-STACK. Source: IIT Kharagpur
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Application Programming Interface (API) -> a set of rules that allow clients and servers to talk to each other. Representational State Transfer (REST) -> a set of rules for developing APIs.
APIs have been written so that a node is capable of the following functions: •
Registering itself with the central server.
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Going offline.
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Updating its latest location, battery level and sensor data.
The front-end part of the full-stack is what a client (end user) sees when attempting to interact with the tool. On logging into the front-end, a map of the region under consideration is displayed with a ‘predict now’ button. A colour overlay would then be displayed on top of the map to indicate the probability of a landslide. Each prediction is stored in the database, making it possible to view prior predictions. The chance of slopefailure as indicated by the various colours are as follows: • • •
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wireless network (2-hop refers to the fact that information is passed from the node to the central server via two intermediate points). Doing so will help establish a means of communication between the nodes on site, and the central servers (using the APIs developed so far). A few final touches to the front-end user interface are also underway with the main goals of improving the analytics and visualization of sensor data. To minimize the cost of hardware used, the team aims to keep the total number of sensors used by the network as small as possible. Hence, another short-term goal of the team is to see if a model can be developed in order to optimize both hardware expenses and the accuracy of predictions. Ideally, such a model would take the topography (of the region we would want to monitor), node density and other related information as inputs, and identify the minimum number of sensors required at each node.
Yellow -> Moderate Red -> High Brown -> Very high
Future Enhancements In the coming months, the team plans to shift their focus to the hardware aspect of the project. One of the main tasks at hand involves combining multiple sensing modules (such as rain sensors, pore water pressure sensors, tilt sensors and GPS modules) along with a solar panel and a rechargeable battery onto a single Arduino-based microcontroller board. The plan is to then integrate Zigbee with this controller board, forming a 2-hop
COLOURED OVERLAY AND NODES ON A MAP OF SHILLONG, MEGHALAYA Source: Land Slide
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The Pixxel Story From a small room in Bits Pilani to becoming one of India’s foremost name in the private space sector, we look at how Pixxel space is rewriting the rulebooks with its advanced hyperspectral imaging smallsats. Written by SHAURYA SHRIVASTAVA Designed by PINNINTI RENU SREE
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he year is 2018. A bunch of undergraduate students from BITS Pilani are working on the IBM Watson AI problem, which is a $5 million competition to solve global challenges using AI. A young Awais Ahmed and Kshitij Khandelwal, while working on the challenge, soon run into a problem. They wanted to predict chlorophyll content in plants among other things using satellite imagery but were handicapped by the lack of high-resolution imagery data for such analysis. The students soon reached out to major companies in the satellite imagery domain to learn more about this problem and soon realised there is a market for a satellite company to offer high-resolution imagery data. This was the start of Pixxel Space, the space tech startup which seeks to solve various problems in climate change and agriculture using hyperspectral satellite imagery.
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Their journey was certainly not an easy one. Awais recalls living at hardly 10k per month, but he restrains from claiming it as a very risky venture at the time. The company was unofficially started one year before their scheduled graduation, which meant it gave it sufficient safety net. Meanwhile, co-founder Kshitij already had a job so they went ahead after Awais burrowed some money from his father to get work started. After being initially started in 2018, the company went for funding stage in July 2019 and received early success by connecting with a BITS alum. This helped them tap into the BITS alumni community which helped them with the initial funding. A few months later, they were selected in the 2019 edition of Techstars Starburst Space Accelerator, which helped them get mentored by the experts in space industry. While it is certainly tough to raise capital in a risky business such as the space industry, tapping into the alumni network was a tremendous start for them. Pixxel space has already raised 40 crore rupees. Furthermore, the founders are grateful to Techstars for introducing them to the best in the space industry. When asked about the biggest challenges they have faced until now in their journey to space,
the young duo elaborated on the regulation uncertainty in the satellite industry. These are several regulation certifications one needs to obtain without which flying is prohibited. Awais is not new to entrepreneurship, neither to the space industry. During his college days, he was a founding member of BITS Pilani chapter of Hyperloop and was also a part of the Anant, the college‘s CubeSat group. As a part of Hyperloop, he was a member of the team which presented at the SpaceX Hyperloop Pod competition, being one of the two teams to do it from Asia. The founders envision a subscription-based model for selling their raw satellite data as a revenue model. While their first satellite, Anand, which has been named so as a tribute to one of the late interns at Pixxel, is a technology demonstration satellite; Pixxel aims to soon expand to have a constellation of satellites to offer real-time imaging of earth and are targetting 80 satellite launches by the middle of 2023. Satellite imagery data can be of immense usage to varied sectors, including agriculture, urban monitoring, climate studies and forestry.
INAUGURATION OF M/S PIXXEL’S OFFICE AT BANGALORE HELD TODAY IN THE PRESENCE OF DR. K. SIVAN, CHAIRMAN, ISRO/SECRETARY, DOS AS CHIEF GUEST. Source: yourstory.com
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SATELLITE CROP MONITORING HYPERSPECTRAL SMALLSAT CONSTELLATION TO PROVIDE UNPRECEDENTED GEOSPATIAL INSIGHTS Source: yourstory.com
While Pixxel had initially planned for a launch aboard the Soyuz rocket, they had to drop that plan during COVID -19 pandemic. The start-up has made other international collaborations including one with ‘Leaf Space’ for ground station operations to help transfer data back to earth. Despite the COVID-19 restrictions, Pixxel has managed to thrive in this abnormal world and has expanded in size. The company has also managed to secure a rideshare launch with ISRO this year and since the orbital parameters are quite similar to the Soyuz missions, this was an easy decision for the founders. The latest changes in the Indian space policy and the set-up of InSpace has definitely boosted India’s presence in the space sector. Given that the space industry in India is still in its infancy, there were major challenges in the production and manufacturing of Anand. For instance, given the absence of space instrument manufacturing companies in India meant they had to practically import most of their components, increasing costs. However, the young duo is hopeful the situation would soon change, especially with the government pushing for private space ventures. And with
many space-tech start-ups burgeoning, the future is not that far when Pixxel uses satellite components like solar panels made in India and even collaborate with private space companies like Skyroot Aerospace and Agnikul Cosmos for future space missions.
PIXXEL SPACE’S FIRST SATELLITE: ANAND Source: yourstory.com
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Writing with optical tweezers: IISER Kolkata’s foundation
Taking a glimpse at the IISER Kolkata’s Optical research team that is spanning the application of the foundation that won the 2018 Nobel Prize in Physics. Written by RAJDEEP SARKAR Designed by KEERTI CHARANTIMATH
henever we are about to execute any scientific experiment we tend to look for some basic pieces of equipment to ease the conduction of our work, ranging from scissors to electron microscopes. Tweezers define a distinct tool, picking objects too small to be easily handled by our fingers. Such a definition is again physically relevant when our focal point of discussion is “Optical-tweezers” where the chore follows holding materials within the size range of a few micro to nanometers. Optical tweezers have been used to trap dielectric spheres, viruses, bacteria, living cells, organelles, small metal particles, and even strands of DNA. First demonstrated in 1986 at Bell labs, optical tweezers now have become an emerging tool in research fields ranging from biophysics to cell biology.
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As the name suggests, they are formed when a laser beam is tightly focussed on a tiny region in space using a microscope objective as a lens. This region becomes an optical trap that can hold small objects in 3D. Around three decades back Arthur Ashkin, an American physicist pioneered the development of a three-dimensional stable trap based on radiation pressure from a single laser beam, capable of holding and applying forces to micron-sized dielectric particles. Which also lead him to win the shared 2018 Noble Prize in Physics. This allows researchers to study the diffusion dynamics of an object in a chemical solution — a property that plays a key role in the functioning of many biological molecules. Simply put, the value of optical tweezers lies in the fact that they can be used to perform experiments to probe the properties of single-molecules by applying forces in the range of picoNewtons and by measuring displacements in the range of nanometers.
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SOURCE: BLOCK LAB, STANFORD UNIVERSITY AND IISER KOLKATA
SOURCE: IISER KOLKATA
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Getting it established In a typical optical-tweezer configuration, the incoming light originates from a focused laser beam through a microscope objective and focuses on a spot in the sample, The spot creates a trap able to hold a small electrically insulating object at the place. The total forces experienced by the object, or bead in most experimental settings, consist of a scattering force and a gradient force. SOURCE: OPTICS LAB, IISER KOLKATA
The scattering force arises when an incident light beam is scattered by the surface of the bead. This scattering produces a net momentum transfer from the light photons to the object and causes the bead to be pushed towards the beam of propagation. The gradient force is a result of the intensity of the laser beam which acts as an attractive force drawing the bead towards the region of greater light intensity. In the case of a highly focused laser beam with a preferred intensity profile, the latter force operates like a restoring force that pulls the object into the center of the focal plane. Diagrams illustrate how the gradient force restores an off-centered bead towards the center of the focal plane, effectively trapping the object in all dimensions.
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Applications and the case of IISER Kolkata It became too unique to mark when researchers at IISER Kolkata developed bubbles advocating the Optical tweezers. They typically produced it by applying large intensity of trapping beam incident in the absorbing material in contact with the sample liquid medium.
SOURCE: OPTICS LAB, IISER KOLKATA
Towards fabricating biomarkers Sometimes the operations with optical tweezers are often compared with the “Star trek tractor beam”, obviously the science fiction series has been talked about where graviton force beams are used to manipulate the objects outside the spaceship. It is because an optical tweezer when placed for applications, behave as similar as that when it grabs proteins or DNA molecules and control their positionings just using light’s momentum. In a recent study, researchers at the Indian Institute of Science Education and Research Kolkata have devised new techniques to create micrometer-sized rods and rings with molecules of diphenylalanine. They have demonstrated that these rods and rings can transmit some specific range of frequencies of light with a minimum energy loss and they can be too used in light-based circuits and devices.
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These days self-assembly processes with diphenylalanine do not use electric or magnetic fields. Instead, the polymers are left to themselves to arrange into required patterns. This process is not only slow but also hard to control. To address this shortcoming, the researchers of the current study had developed a faster ‘laser-assisted self-assembly’ technique. The team has proposed a method that involves dispersing diphenylalanine solution in water in a small glass cell. On top of this cell is a heatabsorbent coating that heats up when a laser beam is focused, to create a water vapor bubble in the solution. While still in cold water, this bubble is stuck to the hot spot on the coating and the difference in the temperature around the bubble creates unequal surface tension, causing the flow of diphenylalanine molecules from the solution to the base of the bubble, the diphenylalanine then crystallizes into beautiful micro-rings at the coating of the bubbles. The intensity of the laser beam controls the size of the bubble, the greater the intensity is, the bigger the bubble, and bigger is the size of the ring. Thus, by adjusting the laser beam, one can control the size and the location at which the micro-ring is formed. The researchers then examined if the micro-rings can transmit specific frequencies of light with minimum energy loss or not. They sent a beam of light from one end and observed it coming out at the other end, they found that the microrings of the same thickness showed the least loss in energy. The energy loss also depends on an optical phenomenon called total internal reflection—where all of the incident light is reflected off a surface beyond a certain incident angle. The researchers have observed that the energy loss of the polymer micro-rings increases when dyed with Congo-red. Hence, it has to be factored in when manufacturing the rings. The study is a step towards incorporating self-assembly techniques to fabricate nano and micro-scale devices. It could also help to develop a diagnostic tool for early detection of Alzheimer’s disease. Congo red dye is specifically used for the detection of
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Alzheimer’s disease. Researchers are trying to make Congo red dye-doped diphenylalanine micro-rings. When these rings bind to the A peptide, which is a protein present in the serum of an Alzheimer’s patient, shows a change in its optical properties and thus in a way helpful to trace the disease. . They are also in search of other varieties of polymers rather than diphenylalanine which could more strongly bind with the protein.
SOURCE: OPTICS LAB, IISER KOLKATA
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Laser
A Flagship of Experimental Physics A short glimpse covering the role lasers have played in experimental physics, viewing them under the lens of research at IIT Hyderabad.
Written by DIVYANSH KHARBANDA Designed by KEERTI CHARANTIMATH
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Introduction Lasers have become a household name due to their usage in many “ordinary” devices in our lives. However this was not always the case and this is surely not their true capability. A brief history of their discovery and a juxtaposition of their past usage across the globe with the future of their use, specifically at IIT Hyderabad, is what this article aims to cover.
History A laser is a device that emits light through a process of optical amplification based on the stimulated emission of electromagnetic radiation. What differentiates a laser from normal light is that the light wave composing a laser is coherent. Lasers were theorized by Charles Hard Townes and Arthur Leonard Schawlow and were brought into existence in 1960 by Theodore H. Maiman. Lasers were a revolutionary invention. A list of their influence across various fields is quite long. Moving beyond their use in everyday appliances, their utility in exploring the extremities of molecular interaction is worthy of thought and discussion, while also being their intended use. Since they are composed of electromagnetic waves, they allow us to interact with charged matter with tremendous precision. This discovery won a Nobel Prize, which does not begin to describe the repercussions they had in the field of physics.
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Freezing Atoms Temperature is linked innately to the random motion of particles. It had been theorized that slowing down this motion to non existent limits would yield temperatures nearing absolute zero. Soon after their discovery, lasers became the tool of choice to turn this into reality. The process by which lasers cool and trap neutral atoms is best described in layman language by William D. Phillips (winner of the Nobel Prize in Physics in 1997) in his Nobel Lecture, quoting Arthur Ashkin as : “He described how one might slow down an atomic beam of Sodium using radiation pressure of a laser beam tuned to an atomic resonance. After being slowed, the atoms would be captured in a trap consisting of focused laser beams, with the atomic motion being damped until the temperature of the atoms reached microkelvin range” These super cooled atoms move like a thick liquid, and hence were termed Optical Molasses. In the experiment conducted in
1985 by Steven Chu (who shared the Nobel Prize with William D. Phillips and Claude Cohen-Tannoudji), Sodium Atoms were super cooled and “captured” at an intersection of 6 laser beams. The temperatures reached were around 240 microkelvin, corresponding to a speed of 30 centimeters per second. To put that into perspective, the atoms and molecules of which air is composed of move at a speed of about 4,000 km/hr (Over a thousand meters per second) at room temperature. The properties of atoms so trapped can be studied with great accuracy. Even their inner structure can be viewed and studied. The development of this method opened new doors for the study of the interplay between radiation and matter. In particular, they opened the way to a deeper understanding of the quantumphysical behavior of gases at low temperatures. In time, laser cooling became the cause of many modern scientific discoveries and technological advancements, including the observation of a new state of matter, the Bose–Einstein condensate. an account of how they are driving scientific exploration is what follows.
THE NOBEL PRIZE IN PHYSICS 1997 AWARDEES Source: NobelPrize.org
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Manipulating Molecules With the rapid development of the technologies based on these theories, lasers have become an irreplaceable tool in the modern engineer’s/ scientist’s arsenal. As hoped and predicted by the scientists during the dawn of this technology, lasers play an invaluable role in the study of matter today. Here at IIT Hyderabad, Dr. Vandana and her team have been leading these efforts in the institute. In her recent work to study the Hindered Alignment in ultrashort, intense laser-induced fragmentation of Oxygen, lasers were used to experiment and come up with a semiclassical model, that described the induced rotation of the molecular ion which involved the polarizabilities of the participating excited states.
Brief Introduction The tendency of a charge distribution to rearrange itself in response to an external electric field is quantified by its polarizability. The polarizability of a molecule also manifests itself in the response to an intense laser field. Despite the ordinarily bound nature of the parent molecular ion states, dissociation of the molecules may occur through laser-induced coupling of the molecules with their higher excited states. In the experiments that were conducted, moderate intensity, 800nm and 400nm wavelength laser pulses were used to ionize and dissociate the oxygen molecules. The resulting field-induced coupling of the parent electronic state with dissociative excited states resulted in fragmentation.
The core phenomena The molecular ion motion is being “frozen” by utilizing the negative polarizability of the molecular ion in a particular state. The driving laser electric field tries to align the molecule in a certain way, but the negative polarizability tries to anti-align it. The molecule thus appears to be frozen when it is in the electric field of the laser.
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DIAGRAMMATIC REPRESENTATION OF THE EXPERIMENT Source: J. Chem. Phys. 152, 014302 (2020); doi: 10.1063/1.5130706
Observations
Conclusion
The direction of ejection of the fragments is influenced by the rotational impulse provided by the trailing part of the laser pulse. This is termed as postionization alignment. With the increasing laser intensities, the observed fragment distribution usually tends to peak along the polarization axis.
The applications of this research expand out into fields beyond physics as well and are being developed simultaneously. Similar research in rescattering photoelectron spectroscopy of CO2 and electron acceleration by transient intense-laser-plasma electrodes are underway as well.
The angular distribution of the fragments is extracted through velocity map imaging of the oxygen cation. The expected alignment was observed in the case of O2 molecules ionized by intense laser pulses of 800 nm wavelength. However when laser pulses of 400 nm wavelength of comparable intensity are employed, an anomalous hindering of this alignment is observed.
Rapid strides in the technology of laser plasma-based acceleration of charged particles leading to high brightness, tunable, monochromatic energetic beams of electrons and ions has been driven by their potential multidisciplinary applications in cancer therapy, isotope preparation, radiography and thermonuclear fusion.
A theoretical semiclassical model was developed to explain these observations. The model stated that a transient negative polarizability of the intermediate state is responsible for hindering the alignment.
The research behind lasers allows experimental physicists to discover more about molecular interaction. This in turn leads to development of better laser based technology. The coherence that is a fundamental property of lasers thus manifests itself in the real life too. The products of this synergy are a lot to look forward to.
LASER LIGHT CAN BE STRETCHED, AMPLIFIED, AND THEN COMPRESSED TO CREATE STRONG, SHORT PULSES OF ENERGY - THE NOBEL PRIZE 2018 WINNING THEORY. Source: Johan Jarnestad/The Royal Swedish Academy of Sciences 29