Lab Updates

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    Emergence of Unconventional Interfacial Spin Texture in Topological Insulator-Based Magnetic Heterostructures Link Link
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    Our in-house integration work: A low noise cryogen-free scanning tunneling microscope superconducting magnet system with vacuum sample transfer Review of Scientific Instruments 92, 023906 Link
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    Virtual online conference series on - Aspects of Condensed Matter Physics in Quantum computing and sensing Link

Who we are.

"The mind that is open to new ideas never returns to its original size." - Albert Einstein


Lab Facilities

We design, assemble and integrate our UHV cluster vacuum systems. Our current system houses interconnected MBE, 8 target turret style DC/RF sputtering, oxygen plasma, ion milling/heating station and LT-STM.

Research areas

Our group research activity spans molecular spintronics, proximity effect studies at hybrid interfaces to explore topological nature of interface states using wide classes of materials viz. topological insulators, superconductors (s-type and pcnictides), ferromagnetic insulators and antiferromagnets.

UHV Cluster system

A custom built interconnected Ultra high vacuum systems for thin film growth and in-situ characterizations. This facility, unique in the country, allows in-situ transfer of samples between dedicated growth and characterization UHV chambers. Working with this sytem provides a unique blende of basic science and technology

Turret-style DC/RF magnetron sputtering system

The in-house designed 8 + 2 target DC/RF turret style sputtering chamber with local gas injection for both inert and reactive sputtering makes this system unique in its design to work on a wide range of material growth with no cross contamination. A chamber base pressure of better than 5x10-9 mbar allows us to work with epitaxial thin films.

Molecular beam epitaxy system

The inhouse designed Molecular beam epitaxy (MBE) system with a base pressure of 5x10-10 mbar has a combination of 5 e-gun evaporation sources, 5 Knudsen cells with RHEED and sample station capable of substrate temperature from ~100K to 1700 K

In-situ Oxygen plasma, heating station and Argon ion milling

The UHV cluster system has dedicated chambers for surface cleaning, controlled oxidation, ion milling for small area samples and heating station upto 2000K for STM surfae preparation

VTI cryostat

The VTI Cryostat with 9T field allows magnetotransport measurements from RT to 1.5K.

Cryogen free LT-STM with 5-1 T vector magnet

Our lab houses the world's first cryogen-free STM with a cryogen_free magnet capable of vertical field of 5T and an in-plane field of upto 1T.

Wire bonder

Al wedge wirebonder

Cleanroom facility with Laserwriter and SEM/EBL

A a part of the shared facility, our cleanroom houses laser writer lithography for maskless patterning, soft lithography and SEM with E-beam lithography


Research Areas

Interface-assisted molecular spintronics

Antiferromagnet spintronics

Malavika, Bhargav

Topological insulators

Topological superconductivity

Ritesh Sachan

Optical coating research for LIGO India

Rajesh Kumar


Members & Alumni

Principal Investigator

Karthik V. Raman, Ph.D 2011 (MIT, USA)

Associate Professor-G (2022- present)
Associate Faculty, DCMP & MS, TIFR Mumbai (2022- present)
Reader-F (2016- 2021)
Fellow-E (2015- 2016)
Ramanujan Fellow, IISc (2013-2015)
Scientist, IBM Research Labs (2011-2013)
AWARDS:
2011-2016 Ramanujan Fellow
2015 PACIFICHEM Early Career Chemist Award
2020 INSA Young Scientist Award
2022 S. N. Seshadri Memorial Instrumentation Award
2022 ACMM Rising Star award

Aathif Ahmedof

Facility Manager

Swapnil Sarjerao Sagare

Scientific Assistant

Prasad Padhye

Project Scientific Assistant

Mugesh B

Project Associate

Ritesh Sachan

Post doctoral fellow

Malavika Chandrasekhar

Post doctoral fellow

Girija Shankar Papanai

Post doctoral fellow

James Wilson

Project student

Alumni

Suman Mundlia (PhD and Postdoc fellow at TIFRH)
Currently a faculty at SRM Institute of Technology, Chennai
Bhargava Rajyaguru (Postdoctoral Fellow at TIFRH)
Currently at Uppsala University, Sweden (Postdoctoral fellow)
Anjan Bhukta (Post doctoral researcher at TIFRH)
Currently a Senior Postdoctoral fellow at IACS Kolkata
Mukil M.(Project Intern Student at TIFRH)
Currently a Ph.D student at MPQ, University Paris Diderot, Paris
Satyaki Sasmal (graduate student at TIFRH)
Postdoctoral Fellow at Niels Bohr Institute, Denmark
Saurabh Chaudhary (graduate student at TIFRH)
Postdoctoral Fellow at Hong Kong Polytechnic University
Dhavala Suri (post doctoral researcher at TIFRH)
Currently a faculty at IISc Bangalore
Joynarayan Mukherjee (post doctoral researcher at TIFRH)
Currently faculty (contractual) at IIEST Shibpur, West Bengal
Soumya Sankar(SRF at TIFRH)
Currently a Ph.D student at HK University of Science and Technology, Hong Kong
S. Mathimalar (post doctoral researcher at TIFRH)
Currently a faculty at SRM institute of Technology
Rajasekhar Pothala (post doctoral researcher at TIFRH)
Currently a faculty at NMIMS Shirpur
Sambit Mohapatra (SRF at TIFRH)
Currently a Ph.D student at University of Strasbourg, France
Swapnil Pathak (SRF at TIFRH)
Currently a Ph.D student at University of Strasbourg, France
Anshika Mishra (JRF at TIFRH)
Currently a Ph.D student at Aalto University, Finland
Rajesh Kumar (JRF at TIFRH)
Currently a Ph.D student at IIT Hyderabad, India
Rita Abani (VSRP at TIFRH)
Currently a Ph.D student at Harvard University
If your name is missing in this list, please drop me an email with your photo.

Joining our Lab !

We are looking for dedicated and self-motivated graduate students, postdoctoral and short-term research scholars who want to build a strong career in experimental condensed matter physics.
  1. Our group has openings for 3 Ph.D/iPh.D students.
  2. If you are a graduate student at TIFR, we strongly recommend you taking part in the Lab activity as early as possible, i.e. in case of PhD student, immediately after your first year of coursework or in the case of iPhD student, immediately after your second year of coursework. Please meet me in my office or email me.
  3. If you are looking for post doctoral position in our lab, please email me with your resume only if you have prior experience in thin film epitaxial growth or in nano/micro fabrication or in cryogenic transport measurements (4K or mK measurements).

Publications

  1. Longitudinal magnetoconductance and the planar Hall conductance in inhomogeneous Weyl semimetals, A Ahmad, KV Raman, S Tewari, G Sharma, Physical Review B 107, 144206, 2023
  2. Decoupling intranode and internode scattering in Weyl fermions, G Sharma, S. Nandy, K. V Raman and S. Tewari, Physical Review B 107, 115161, 2023.
  3. Emergence of Unconventional Interfacial Spin Texture in Topological Insulator-Based Magnetic Heterostructures, Dhavala Suri, Archit Bhardwaj, Satyaki Sasmal, Karthik V. Raman, arXiv preprint, 2021
  4. In-depth Analysis of Anisotropic Magnetoconductance in Bi2Se3 thin films with electron-electron interaction corrections, S Sasmal, J Mukherjee, D Suri, Karthik V Raman, Journal of Physics: Condensed Matter, 33, 46, 2021
  5. Observation of Planar Hall Effect in Topological Insulator -- Bi2Te3, Archit Bhardwaj, Syam Prasad P., Karthik V Raman, Dhavala Suri, Applied Physics Letters, 118, 241901, 2021
  6. An all cryogen-free integration of scanning tunneling microscope with superconducting vector magnet in a vacuum cluster assembly with low spectral noise, Saurabh Chaudhary, Janmey Panda, Suman Mundlia, S. Mathimalar, Aathif Ahmedof, and Karthik V. Raman, Review of Scientific Instruments, 92, 023906, 2021
  7. Sign reversal of anomalous Hall conductivity and magnetoresistance in cubic noncollinear antiferromagnet Mn3Pt thin films, J. Mukherjee, T. S. Suraj, H. Basumatary, K. Sethupathi, and K. V. Raman, Phys. Rev. Materials, 5, 0124201, 2021
  8. Robust monolayer exchange-bias effect in molecular crane-pulley response at magnetic surface, S. Mundlia*, S. Chaudhary*, L. Peri, A. Bhardwaj, J. J. Panda, S. Sasmal and K. V. Raman, Phys. Rev. Appl., 14, 024095, 2020 (* equal contribution)
  9. Signature of gate-controlled magnetism and localization effects at Bi2Se3/EuS interface, S. Mathimalar*, S. Sasmal*, A. Bhardwaj, S. Abhaya, R. Pothala, S. Chaudhary, B. Satpati and K. V. Raman, npj Quantum Materials, 5, 64, 2020 (* equal contribution)
  10. Probing Proximity-Tailored High Spin-Orbit Coupling in 2D Materials, K. R. Sahoo, T. P. Chakravarthy, R. Sharma, S. Bawari, S. Mundlia, S. Sasmal, K. V. Raman, T. N. Narayanan, N. K. Viswanathan, Adv. Quantum Technologies, 2000042, 2020
  11. Observation of zero bias conductance peak in topologically trivial hybrid superconducting interfaces, S Mohapatra, S Mathimalar, S Chaudhary and K V Raman, Jour. of Phys. Comm., 3, 4, 2019
  12. “Materials chemistry: A magnetic facelift for non-magnetic metals,” Karthik V. Raman, Jagadeesh S. Moodera. Nature, 524, 42, 2015
  13. “On the Origin of Steep IV Nonlinearity in Mixed-Ionic-Electronic-Conduction-Based Access Devices,” A. Padilla, G. W Burr, R. S Shenoy, K. V Raman, D. S Bethune, R. M Shelby, C. T Rettner, J. Mohammad, P. Narayanan, A. K. Deb, R. K. Pandey, M. Bajaj, KVRM Murali, B. N. Kurdi & K. Gopalakrishnan. IEEE Transactions on Electron Devices, 62, 963, 2015
  14. “MIEC (mixed-ionic-electronic-conduction)-based access devices for non-volatile crossbar memory arrays,” R. S Shenoy, G. W Burr, K. Virwani, B. Jackson, A. Padilla, P. Narayanan, C. T Rettner, R. M Shelby, D. S Bethune, K. V Raman, M. BrightSky, E. Joseph, P. M Rice, T. Topuria, A. J Kellock, B. Kurdi & K. Gopalakrishnan. Semicond. Sci. Technol., 29, 104005, 2014
  15. “Tailoring ferromagnet-molecule interfaces: towards molecular spintronics,” Karthik V. Raman, N. Atodiresei & J. S. Moodera. SPIN, 04, 1440014, 2014
  16. “ Interface-assisted spintronics: Tailoring at the molecular scale,” N. Atodiresei & Karthik V. Raman. MRS Bulletin, 39, 596, 2014
  17. “ Interface-assisted molecular spintronics,” Karthik V. Raman. Appl. Phys. Rev., 1, 031101, 2014
  18. “ Focusing on the molecular scale,” Karthik V. Raman. Nature Nanotech., 8, 886, 2013
  19. “Interface engineered templates for molecular spin memory devices,” Karthik V. Raman, Alexander M. Kamerbeek, Arup Mukherjee, Nicolae Atodiresei et al. Nature, 493, 509, 2013
  20. “New method of spin injection into organic semiconductors using spin filtering tunnel barriers,” K. V. Raman, J. Chang, J. S. Moodera. Org. Electronics, 12, 1275, 2011
  21. “ Effect of molecular ordering on spin and charge injection in rubrene,” K. V. Raman, S. M. Watson, J. H. Shim, J. A. Borchers, J. Chang, J. S. Moodera. Phy. Rev. B, 80, 195212, 2009
  22. “Determining exchange splitting in a magnetic semiconductor by spin-filter tunneling,” TS Santos, JS Moodera, KV Raman, E Negusse, J Holroyd, J Dvorak, M Liberati, YU Idzerda, E Arenholz. Phys. Rev. Lett., 101, 147201, 2008
  23. “Large spin diffusion length in an amorphous organic semiconductor,” JH Shim, KV Raman, YJ Park, TS Santos, GX Miao, B Satpati, JS Moodera. Phys. Rev. Lett., 100, 226603, 2008

Patents

  1. Cryogenic Apparatus and An Interconnected Network Thereof for Multi-Core Quantum Processor Architecture, K. V. Raman, D. Suri, A. Ahmedof - Indian Prov. App. No. 202021047505 (2020).
  2. Low Power thermal imager, Karthik V. Raman & KVRM Murali US Patent No. 20140361397A1 (2015).
  3. Method of modeling concentration of reducible mobile ionic dopants in semiconductor device simulator, Karthik V. Raman, Mohit Bajaj & Stephen Furkay, US Patent Application No. 20150192533 (2015).
  4. High density molecular memory storage with read and write capabilities, Karthik V. Raman & J. S. Moodera, WO Patent 8,711,600 (2013).

Services

With our in-house expertise in design, manufacturing and assembly of Ultra high vacuum system, its peripherals and cryogenics we offer cost-effective solution to a number of laboratory accessories. Our custom design solutions include MBE, sputtering, Knudsen cell, Magnetic manipulators and others. Some of our in-house designed systems can be seen below.

We also offer coating services for Gold, Tantalum, Platinum, Vanadium. For any other coating requirements, please contact us.

MBE system
Turret-style DC/RF magnetron sputtering system
K-Cell

GET IN TOUCH

Dr. Karthik V. Raman
Tata Institute of Fundamental Research,
Hyderabad, India
P: (+91) 040 2020-3062