“Infinities and indivisibles transcend our finite understanding, the former on account of their magnitude, the latter because of their smallness; Imagine what they are when combined.”

– Galileo Galilei.

The Postgraduate and Research Department of Physics has achieved the enviable distinction of being one of the oldest and largest departments at St. Xavier’s College (Autonomous), Kolkata. Father Eugene Lafont, a brilliant scientist and educator who played a pioneering role in popularising science in and around Calcutta, set the groundwork for it in the middle of the nineteenth century. Other Jesuit fathers with notable academic accomplishments namely Fr. Verstraeten and Fr. Bonhome, have greatly benefited the department in many ways. This department has been offering a post-graduate physics course since 2006 in addition to the undergraduate courses (honours and pass). A PhD programme, under the supervision of its faculty members, was initiated in the department in 2016. Since July 2018, this department has been running the B.Sc. course under the CBCS curriculum introduced by the UGC. A new choice-based syllabus for the M.Sc. course has been introduced in the current year.

The department’s faculty members are highly skilled, knowledgeable, and devoted to providing quality education in the best manner possible. The majority of them have taken a leading role in cutting-edge physics and cross-disciplinary research. They have published research articles for numerous scholarly journals and have been invited to give lectures on their areas of expertise at a variety of academic institutions. Some of their work has also claimed patent rights.

The Science Academies’ Lecture Workshop, jointly organized by The National Academy of Sciences, The Indian National Science Academy and the Indian Academy of Sciences are held in the department of physics on a regular basis. The Fr. Verstraeten Memorial lecture is also an annual lecture organised by the department with eminent scientists as invited speakers. The Physics department have also held a one of its kind refresher course in experimental physics jointly with the Indian Academy of Science with faculty members as resource persons. In association with FELO, several serial workshops like JESCOL and RAWA were held in previous years. In recent years, the department of Physics have also initiated the Dr.Ranjan Ray Commemoration Seminar and Fr. Eugene Lafont memorial Lecture.

The M.Sc. course includes the teaching of sophisticated computer programming and computer interfacing using the languages of Matlab and Python.

The special papers offered by the department for the M.Sc. course in Physics are:

(1) Astro-particle Physics

(2) Condensed Matter Physics

After lying dormant for more than a century, under the able guidance of the erstwhile Principal Fr. Mathew and enthusiasm of some faculty members of the Physics department, initiatives were taken to restart scientific activities in the observatory around 2007, with the old telescope and some make shift arrangements. This was in coincidence with the opening of the post-graduate course in Physics, with special emphasis on Astro-particle Physics, in collaboration with Bose Institute, Kolkata. The Department of Physics manages the Father Eugene Lafont Observatory, with the Principal being its director,  Dr. Shibaji Banerjee , being its Assistant Director and Dr. Suparna Roy Chowdhury, currently. It is the oldest and the biggest observatory housed on an educational campus in India. A part of the research in astrophysics is carried out in Father Eugene Lafont Observatory (FELO) which is a twin observatory consisting of a stellar observatory with a motorized dome and a separate sliding roof observatory meant for solar observations.

Condensed Matter Physics Laboratory has many electronics based experimental units related to both analogue and digital communications, fibre optics and microcontrollers. Hall effect measurements and magneto-resistance setups are also included.

Academic activities of the department has been included in the report from ISRO on ‘Space Research in India’ for 44th COSPAR Scientific Assembly held between 16th – 22nd July, 2022, at Athens, Greece.

1. National Science Day was celebrated on 28^th February, 2022 virtually. The keynote speaker for the webinar was  Bhupati Chakrabarti.  Father Principal graced the occasion and delivered the inaugural address.
2. On 4th February,2022 at Dr Ranjan Ray Commemoration, Dr Tirtha Pratim Das, Director of Science Programme Office, ISRO Headquarters, Bangalore, ISRO, delivered a lecture on “Space Science Exploration Programme in ISRO”.The students of St. Xavier’s College (Autonomous), Kolkata, as well as students from various colleges from all over India attended the webinar.
3. 13^th Annual Departmental Fest “Spectrum: Beyond the Monochrome” was held on ZOOM and streamed on YouTube on 26^th March, 2022. It was viewed by many ex-students of the department from different corners of the world.
4. 1^st offline post-pandemic event, 1^st Father Eugene Lafont Memorial Lecture was held on 17^th of August, 2022, in association with DBT Star College Programme.The lecture was organised in memory of Fr. Eugene Lafont, the pioneer of experimental science in pre-independent India and a missionary assigned to set up St. Xavier’s College in 1860. The guest lecturers were Ms. Madhuri Katti, teacher of Physics and Global Perspectives, Modern High School, Kolkata, and Prof. Puragra Guha Thakurata, Astronomer and Departmental Chairperson of The Department of Astronomy and Astrophysics, University of California, Santa Cruz. The title of their lectures were“Father Eugene Lafont: A Priest, An Experimentalist and a Pioneering Science Mentor”, and “The Universe of Galaxies, James Webb Space Telescope, and STEM Research Opportunities for the Young” respectively.
5. “Teachers’ Day 2022”, a colourful and exuberant cultural programme was organized by the students on 5^th September, 2022 to pay respects and gratitude to their Professors and Laboratory Staff.
6. On 16^th September, 2022 a special seminar was organized on the topic “Quantum Materials by Computation: Challenges & Opportunities”, which was delivered by Dr.Tanusri Saha-Dasgupta, Director, Department of Condensed Matter Physics & Materials Science Thematic Unit of Computational Materials Science, S. N. Bose National Centre for Basic Sciences, Kolkata.
7. On 25^th November, 2022 a Faculty Development Programme was organized on the topic “Application of Density Functional Theory in Condensed Matter Physics”, which was delivered by Dr.Debnarayan Jana, Professor, Calcutta University and Dr.Bhimaleengam Chittari, Assistant Professor, IISER, Kolkata.
8. On 7^th December, 2022, a special lecture was organized where Dr. Marie-Gabrielle MEDICI delivered a talk on “Dew condensation and Harvesting – Potential source of drinking water. New challenge for some arid countries.”
9. Departmental Scholarship to students:Pradeep P. V. (from UG)and Avijit Sen Majumder (from PG) received the scholarship.
10. Students Webinar/Seminar Organized by the Department:

• Samarjit Chakraborty, a PhD student, gave a talk on “Gravity and Thermodynamics” on 25^th February 2022.
• Ashadul Halder, after getting his Ph.D degree gave a talk on “Dark Matter and Global 21-cm Signal” on 1^st April 2022.
• Ruhul Amin Ibne Haque, a PhD student, gave a talk on “Combinatorial Topology and Geometry of Fracture networks” on 13^th May 2022.
• Sourav Chowdhury, a PhD student, gave a talk on “A Study of the Dynamics of Infectious Diseases” on 18^th November 2022.

1. A one-day international workshop on coarse geometry was organized on 16th August 2019 by the department of Physics in collaboration with Department of Mathematics of St. Xavier’s College, Kolkata. The speaker was Dr. Atish J. Mitra of Department of Mathematics, Montana Tech (University of Montana), USA.
2. On 29th August 2019 Department of Physics conducted national workshop on “Role of DFT in predicting electronic structures and reaction pathway” in collaboration with Department of Chemistry. Prof. Swapan K. Pati of JNCASR and Dr. Anoop Ayyappan of Dept. of Chemistry, IIT Kharagpur delivered lectures in the workshop.
3. In 16th and 17th December 2019 Department of Physics along with Department of Statistics in collaboration with IUCAA centre for astronomy research and development organized a two-day national seminar on “Application of Statistics in Natural Sciences”. The invited speakers who delivered talk in the seminar were Prof. Mihir Arjunwadkar of Pune University, Prof. Saurabh Ghosh of ISI Kolkata, Prof. Supratik Pal of ISI Kolkata, Prof. Rajesh Kumble Naik of IISER Kolkata and Prof. Ayanendranath Basu of ISI Kolkata.
4. A two-day DBT sponsored Faculty Development Programme was organized on 10th and 11th January 2020 on Experimental Physics at Graduate Level: Scopes and Challenges.

(Physics Hons. 2017-2020 batch)

Ayshi Mukherjee has obtained All India Rank 11 in Joint Admission Test (JAM) Physics paper. She also obtained All India Rank 12 in Joint Entrance Screening Test (JEST) Physics paper.

In the month of January 2020, the NGPE exam organized by IAPT was held in our college and she was one of the Top 25 students and hence, she qualified for the next level of the examination which was an experimental round.  She was declared as a NGPE Gold Medalist and eligible for a cash prize of Rs. 20,000/-.

C B S Socrates, Anindita Sarkar and Ayantika Saha are also among the NGPE – 2020 National toppers.

Ayshi Mukherjee joined Tata Institute of Fundamental Research (Mumbai). Aryaa Dattamunsi and Rahul Saxena joined IIT(ISM) Dhanbad. Anindita Sarkar joined IIT Madras. Supritha Bhowmick joined IISER Pune. Ayantika Saha and Avishuman Ray joined IIT Kanpur. Aritra Paul joined IIT Bhubaneswar, Sounak Sengupta and Sharmistha Baidya joined IIT Guwahati, Tamoghna Roy joined ICTS, Bangalore, Debapriya Sil and Debangan Maji joined University of Calcutta, Biju Saha joined Jawaharlal Nehru University, Sounak Samanta joined IIEST, Shibpur, Ayaskanta Ghosh joined NIT, Warangal, Sarbajit Dutta joined JNCASR, Bangalore, Animesh Maji joined Benaras Hindu University, Writabrata Sengupta joined Presidency University, Kolkata (as JRF under Project Funded By Board of Research in Nuclear Sciences), Ilika Banerjee, Siddhartha Sen, Ankit Kumar Gupta, CBS Socrates, Apratim Ghosal and Hrishav Das are continuing there studies at St. Xavier’s College (Autonomous), Kolkata.

Shaashwat Saraf joined dept. of Materials Science and Metallurgy, University of Cambridge, Selwyn College to pursue M.Phil in Micro and Nanotechnology Enterprise in the year 2021.

(Physics Hons. 2018-2021 batch)

1. Pratul Manna – NGPE 2021 , National topper in top 25
2. Sulagna Dutta – NGPE 2021, National topper

3.M.S.Dinesh – AIR 79 in JAM 2021

4. 4. Mehraj Chhetri – AIR 81 in JAM 2021
5. 5. Debonita Saha- Summer Internship, Bose institute, 2019
6. 6.  Kaushik Pal – IUCAA summer school in May 2021

Mousumi Mitra joined IIT Gandhinagar. Sulagna Dutta joined Tata institute of fundamental research, Mumbai for  Integrated Phd in Condensed matter physics , Shramana Bera, Rivu Kayal, Anwesha Ganguly, Debalina Kar, Indranil Kuthe, Kobid Deb Roy, Manisha Dutta, Varsha Biswas, Arup Ghosh, Sayantani Banerje,  and Wrik Banerjee joined St. Xavier’s College, Kolkata, Debraj Dutta joined Satyendranath Bose National Center For Basic Sciences for Integrated PhD programme, Subham Das and  Md Sariful Islam joined IIT KANPUR,  Sagnik Ray joined IISER Thiruvananthapuram for Integrated PhD, Nilabja Ghosh joined M.Sc. in Big data analytics Ramakrishna Mission Vivekananda Educational and Research Institute, Mehraj Chhetri and M.S.Dinesh joined IIT Madras.

1. Sarbari Guhaand Samarjit Chakraborty, published a paper on 24^th March 2020 in International Journal of Modern Physics D (Vol. 29, issue 05 (2020) pp. 2050034.)
2. Samarjit Chakraborty and Sarbari Guha, published a paper on 27^thNovember 2019 in General Relativity and Gravitation ( 51, issue 11 (2019) pp. 158)
3. Gayatri Banerjee, published a paper on 30^th August 2019 in Materials Today Proceedings (Volume 18, Part 2, Pages 494 – 500)
4. Atasi Chakraborty¹, Arup Chakraborty¹, Soma Ghosh², Indra Dasgupta¹, published a paper on 20^th January 2020 in Condensed Matter (Volume — 32, Number — 16, Page — 165802 (9pp))
5. Desiccation cracks formed in Laponite® suspensions of varying pH: aid to analyzing clay microstructure. S Haque, S Tarafdar, T Dutta, Physica Scripta 95 (8), 085703, 2020, IF: 1.985
6. Branched crack patterns in layers of Laponite® dried under electric fields: Evidence of power-laws and fractal scalin. A Ghosh, T Dutta, S Tarafdar, AK Ghosh, The European Physical Journal E 43 (6), 1-6, 2020, IF: 1.812
7. Memory of rheological stress in polymers using Fractional Calculus. A Bhattacharyya, P Nandi, S Hazra, T Dutta, arXiv preprint arXiv:2001.06620, 2020
8. Narrowing Desiccating Crack Patterns by an Azeotropic Solvent for the Fabrication of Nanomesh Electrodes R Pujar, A Kumar, KDM Rao, S Sadhukhan, T Dutta, S Tarafdar, Langmuir 35 (49), 16130 -16135, 2019, IF: 3.557
9. A spring network simulation in three dimensions for designing optimal crack pattern template to fabricate transparent conducting electrodes. S Sadhukhan, A Kumar, GU Kulkarni, S Tarafdar, T Dutta, Bulletin of Materials Science 42 (5), 1-14,2019, IF: 1.392
10. Subhankar Ghosh, published a paper ‘Optimization of Rare Earth (Er3+) Doping Level in Lead Zinc Phosphate Glass Through Judd-Ofelt Analysis on 1st May 2020 in Materials Chemistry and Physics (SCI: Elsevier) (Vol 246, P – 122802)
11. Triloki Prasad, Subhankar Ghosh and Asis Goswami “Static Balance Ability of Visually Impaired and Partially Sighted Persons on Firm and Foam Surfaces” in press, EUJAPA, 8^th May 2020 doi: 10.5507/euj.2020.002 (SCIMAGO h-index 4 )
12. Madhurima Pandey, Debasish Majumdar, Ashadul Halder, and Shibaji Banerjee, published a paper on 10th October 2019 in Physics Letters B (Volume 797, Page 134910)
13. Subhankar Ghosh‘Scientific Activities of Fr. Alphonso De Penaranda: A Jesuit Priest in the late Nineteenth Century’, Indian Journal of History of Science, 54.2 (2019) 215-217 DOI: 10.16943/ijhs/2019/v54i2/49664
14. Triloki Prasad, Subhankar Ghosh and Asis Goswami “Walking Pattern of Sighted Volunteers with Open Eye and Closed Eye Conditions” JODYS, July 2019
15. Sarbari Guha and Sucheta Datta, Axial Gravitational Waves in Bianchi I Universe, International Journal of Modern Physics D, 29, (2020) 2050116.
16. Sarbari Guha and Samarjit Chakraborty, On the gravitational entropy of accelerating black holes, International Journal of Modern Physics D, 29, (2020) pp. 2050034.
17. Impact of varying preparation methods of colloidal suspensions on droplet desiccation patterns on hydrophobic and hydrophilic substrates. A Khatun, S Haque, S Tarafdar, T Dutta, Physica Scripta 96 (2), 025211, 2020,
18. Understanding flow features in drying droplets via Euler characteristic surfaces–A topological tool A Roy, RAI Haque, AJ Mitra, MD Choudhury, S Tarafdar, T Dutta, Physics of Fluids 32 (12), 123310,2020,
19. Addressing gamma-ray emissions from dark matter annihilations in 45 milky way satellite galaxies and in extragalactic sources with particle dark matter models: Banerjee, A. Halder, M. Pandey and D. Majumdar, 2020, Monthly Notices of the Royal Astronomical Society 500 5589
20. Lower bounds on dark matter annihilation cross-sections by studying the fluctuations of 21-cm line with dark matter candidate in inert doublet model (IDM) with the combined effects of dark matter scattering and annihilation: Banerjee, R. Basu, M. Pandey and D. Majumdar 2020, arXiv:2010.11007
21. Chandrasekhar limit for rotating quark stars: Banerjee, A. Halder,S. K. Ghosh and S. Raha, 2021, Phys. Rev. C 103 035806
22. Bounds on Abundance of Primordial Black Hole and Dark Matter from EDGES 21cm Signal: Banerjee, A. Halder, 2021, Phys. Rev. D 103 063044
23. Beyond-Newtonian dynamics of a planar circular restricted three-body problem with Kerr-like primaries, S De, S Roychowdhury, R Banerjee Monthly Notices of the Royal Astronomical Society 501 (1), 713-729
24. Universality and herd immunity threshold: Revisiting the SIR model for COVID-19, S Chowdhury, S Roychowdhury, I Chaudhuri, International Journal of Modern Physics C, (2021) 2150128

Invited Lectures

1.Dr. Tapati Dutta, delivered a lecture in the International conference ‘Droplets 2019’,16-18 September 2019:  Durham, UK

2. Dr. Subhankar Ghosh delivered DBT sponsored lecture at Jhargram Raj College 25th Feb 2020
3. Dr. Subhankar Ghosh regularly delivered talk for the INSPIRE Program held at JBNSTS, Kolkata in 2019-2020.
4. Dr. Suparna Roychowdhury delivered a Seminar at Presidency University, Dept of Physics, or 3rd April. Title: Galaxy Clusters & Active Galaxies – an Explosive Rendezvous
5. Dr. Suparna Roychowdhury delivered a seminar at Uniexplore 2019, Vivekananda College, Kolkata (one day seminar)  on 7th November, 2019 Title: The Cosmic Symphony – Hum of Creation!
6. Dr. Sarbari GuhaInvited speaker and Member of the International Scientific committee at the International Symposium on “Nonlinear Dynamics” organized by the Mathematical Institute of the Serbian Academy of Sciences and Arts, in Belgrade during September 2019.
7. Dr. Sarbari GuhaPresented an Invited talk entitled “Non-Linear Dynamical Systems in General Relativity and Cosmology”, at the International Symposium on “Nonlinear Dynamics”, Belgrade, Serbia, 04-06 September 2019.
8. Dr. Sarbari GuhaDelivered an Invited Lecture on “Some Aspects of General Relativity and Cosmology“, at the Mathematical Institute of Serbian Academy of Sciences and Arts, Belgrade, on September 09, 2019.
9. 9.  Dr. Sarbari GuhaScientifically interacted with the faculty members, students and postdoctoral fellows at the Serbian Academy of Sciences and Arts, Belgrade, Serbia, during 9^th and 10^th September, 2019.
10. Dr. Sarbari GuhaPresented an Invited Lecture entitled “The problem of Gravitational Entropy” in the One-day seminar on “Gravity, Cosmology & Astrophysics – Recent Trends in Research”, at the Department of Physics, Jadavpur University, on 6th March 2020.
11. Dr. Sarbari Guha  Presented Five papers at the International Conference on Gravitation and Cosmology (ICGC 2019) at IISER Mohali, during 10^th to 13^th December, 2019, including one invited lecture entitled “Generalized Second Law of Thermodynamics in FRW Universe with Chaplygin Gas Models”.
12. Statistical modelling of drying droplets —Tapati Dutta , 29-30^th June, 2020; Webinar on Droplets and their drying patterns, Organised by CUTN.
13. Flow features in drying droplets via Euler characteristic surfaces–A topological tool-Tapati Dutta, 11^th January, 2021, Condensed Matter Research Centre, Jadavpur University.
14. Chandrasekhar limit for quark stars: A model building approach
    19th December, 2020, Bose Institute (The Centre for Astroparticle Physics and Space Science (CAPSS)) by Dr. Shibaji Banerjee
15. Beyond Newtonian Dynamics of a planar Circular-Restricted Three-Body Problem with Kerr-like primaries, invited lecture at University Oldenburg – Online, Speaker: Suparna Roychowdhury (St. Xavier’s College Kolkata, India), date: 26th January, 2021.

Outreach Activities (Popular Lectures):

1. Lecture for School Children on Learning Physics through Games & Sports JBNSTS, Kolkata, WBDS in July, 2020 by Dr. Subhankar Ghosh

Patents:

1. Design (No 313731-001) of “MULTI-DIRECTIONAL BALANCE TEST EQUIPMENT” registered on 22.01.2021 (at RKMVERI, Belur)
2. Dr, Subhankar Ghosh has a Design Patent (GOI): dated 15.05.2019

No 305795″Audio game Set for the Visually Challenged” in collaboration with RKMVERI, Belur Math

Training received by the faculty:

1. Aditi Ghosh has successfully completed a course titled “Effective and Efficient Online Teaching in the Age of Corona, A Hands On Workshop” organised by Teaching Learning Centre (ICT) at IIT Bombay on 17th May,2020.
2. Sanghamitra Das participated in ‘The BodhiTree and SAFE Tools for Effective Online Teaching: A Hands-On Workshop’ on 21 June 2020
3. Sanghamitra Das successfully completed the course on online teaching skills between 15 June,2020 — 20 June,2020.
4. Sanghamitra Das has enrolled for the course titled “Refresher Course on Teacher and Teaching in Higher Education” on SWAYAM for ARPIT 2020’ (Duration Dec 2020-Mar 2021).
5. Aditi Ghosh has enrolled for the Refresher Course (ARPIT) on “Introduction to Quantum Physics and its Applications” organised by SWAYAM Team (Duration Dec2020-Mar2021).