Spin Microscopy Lab


Nitrogen-vacancy (NV) defects in diamond crystals are playing an essential role in the development of new nanoscale sensing devices based on the quantum properties of NV defects. We are occupied with the following endeavours:

  • How can the quantum properties of the NV defect spin be controlled for improved quantum sensing tasks?
  • What new nanoscale magnetic field sensing modalities can NV defects enable?
  • How can we apply the NV nanomagnetometry toolbox, which offers high sensitivity and high spatial resolution, for the study of magnetic samples such as 2D magnetic materials having nanoscale volumes?

News

July 2023

December 2022

March 2022

  • Ph.D. student Shashank Kumar gave an online contributed talk at the APS March Meeting in Chicago.

December 2021

Dr. Phani Kumar

Principal Investigator

Research Interests

Nitrogen-vacancy (NV) spins in diamond, Quantum sensing, Atomic force microscopy, Nano-spin-mechanical systems (NSMS), Nanomagnetism, Hybrid quantum sensors, Nanoscale scanning diamond probes, Magnetic resonance imaging, Biosensing, Quantum technology, Confocal microscopy, Laser interferometry


Academics

Postdoc [July 2013 - November 2017]

Institute for Quantum Optics, University of Ulm, Germany

Advisor: Prof. Fedor Jelezko

Research: Quantum Sensing, Diamond Magnetometry, Nano-spin-mechanical Systems (NSMS)

Section on Quantum Physics and Information Technology, Technical University of Denmark, Copenhagen

Advisor: Prof. Ulrik Andersen

Research: Nanomechanics

Division of Physics and Applied Physics, Nanyang Technological University, Singapore

Research: Spin Centers in Silicon Carbide


PhD [Department of Physics, University of Basel, Switzerland (April 2009 - June 2013)]
Thesis: Magnetic resonance force microscopy: Harnessing nuclear spin fluctuations.
Advisor: Prof. Martino Poggio
Research: Apart from making contributions to setting up of a low temperature high vacuum magnetic resonance force microscopy (MRFM) setup, I explored a novel approach using MRFM to harness the naturally occurring random fluctuations in nanoscale ensembles of nuclear spins.


MSc [Micro and Nanosystems, ETH Zurich, Switzerland (October, 2006 - January, 2009)]
Thesis: Efficient coupling to photonic crystal cavities.
Advisor: Prof. Atac Imamoglu
Courses Credited:
Quantum Mechanics for Nanosystems, Advanced Optoelectronics, Quantum Optics, Quantum Systems for Information Technology, Magnetism: from the Atom to the Solid State, Advanced Solid State Physics, Statistical Physics, Semiconductor Nanostructures, Quantum Optics and Semiconductor Quantum Dots
Course Projects:
MATLAB simulations for gain calculations of quantum dot laser


BTech [Indian Institute of Technology, Madras (September, 2001 - July, 2005)]
Courses Credited: (GPA - 8.56/10)
Physics - I, Physics Lab - I, Electrodynamics, Physics Lab - II, Quantum Mechanics for Engineers, Semiconductor Physics, Dynamical Systems, Laser Theory, Mathematical Physics, Superconductivity and its Applications



Achievements

  • Pratibha scholarship awarded by Andhra Pradesh state government for BTech studies in IIT Madras
  • Indian Institutes of Technology-Joint Entrance Examination (IIT-JEE) 2001 Rank: 532 (out of 1,70,000+ students) for admission to IITs
  • Secured an All India Rank of 8 (99.81 percentile) in Joint Entrance Screening Test (JEST) Physics 2009 for admission to Ph.D programmes
  • Achieved a score of 890/1000 (90 percentile) in GRE Physics 2005, an examination taken by applicants for admission into graduate schools in USA

Research

SINGLE-SPIN MAGNETOMETRY


We develop nitrogen-vacancy (NV) spin-based diamond magnetometers capable of measuring the minute magnetic fields with high sensitivity and spatial resolution. Our aim is to utilize the diamond spins as scanning probes to spatially map the tiny magnetic fields on the nanoscale. This would allow us to obtain a greater understanding of the magnetic phenomena which are otherwise not discerned by global magnetization measurements due to spatial averaging.

Scanning Diamond Magnatometer

HYBRID NV-DIAMOND SENSORS


We also apply NV centers as nanoscale probes of stress, temperature and electric fields. Standard NV-diamond sensing devices when combined with the strategy of hybridization offer a huge potential for improving their sensitivity. Such hybrid quantum sensors may provide a novel approach for studying a broad range of physical processes on the nanoscale.

Publications

High-resolution spectroscopy of a single nitrogen-vacancy defect at zero magnetic field

Shashank Kumar, Pralekh Dubey et al.

Quantum Sci. Technol., 2023, 8, 025011 pdf

January 2023

Scalable fabrication of single silicon vacancy defect arrays in silicon carbide using focused ion beam

Junfeng Wang, Xiaoming Zhang, Yu Zhou, Ke Li, Ziyu Wang, P. Peddibhotla, Fucai Liu, Sven Bauerdick,Axel Rudzinski, Zheng Liu, and Weibo Gao

ACS Photonics, 2017, 4(5), 1054-1059

April 2017

Nanomechanical sensing using spins in diamond

M. S. J. Barson , P. Peddibhotla , P. Ovartchaiyapong, K. Ganesan, R. L. Taylor, M. Gebert, Z. Mielens,B. Koslowski, D. A. Simpson, L. P. McGuinness, J. McCallum, S. Prawer, S. Onoda, T. Ohshima, A. C.Bleszynski Jayich, F. Jelezko, N. B. Manson and M. W. Doherty

Nano Lett. (2017), 17 (3), 1496-1503

February 2017

Boundary between the thermal and statistical polarization regimes in a nuclear spin ensemble

B. E. Herzog, D. Cadeddu, F. Xue, P. Peddibhotla and M. Poggio

Appl. Phys. Lett.105, 043112 (2014)

August 2014

Harnessing nuclear spin polarization fluctuations in a semiconductor nanowire

P. Peddibhotla, Fei Xue, H. I. T. Hauge, S. Assali, Erik P. A. M. Bakkers and M. Poggio

Nature Physics 9, 631-635 (2013)

August 2013

Feedback cooling of cantilever motion using a quantum point contact transducer

M. Montinaro, A. Mehlin, H. S. Solanki, P. Peddibhotla, S. Mack, D. D. Awschalom and M. Poggio

Appl. Phys. Lett. 101, 133104 (2012)

September 2012

Measurement of statistical nuclear spin polarization in a nanoscale GaAs sample

Fei Xue, D. P. Weber, P. Peddibhotla, and M. Poggio

Phys. Rev. B 84, 205328 (2011)

November 2011

A geometry for optimizing nanoscale magnetic resonance force microscopy

Fei Xue, P. Peddibhotla, M. Montinaro, D. P. Weber, and M. Poggio

Appl. Phys. Lett. 98, 163103 (2011)

April 2011

Members

PhD Students



Name: Shashank Kumar

Email: shashankk19[AT]iiserb.ac.in

Joined: January, 2020


Name: Pralekh Dubey

Email: dpralekh[AT]iiserb.ac.in

Joined: August, 2021


BS-MS Students



Name: Yash Patel

Email: yash19[AT]iiserb.ac.in

Joined: September, 2023


Name: Devang V Krishnan

Email: devang19[AT]iiserb.ac.in

Joined: June, 2023


Project Fellow



Name: Anshul Poonia

Email: anshulpoonia1996@gmail.com

Joined: June, 2023


Alumni


BS-MS Students
  1. Alen Philip (Graduated from IISERB in 2019, Currently Graduate Student at the Institute of Optics, University of Rochester)
  2. Basim S. S. (Graduated from IISERB in 2019)
  3. Md Arshad (Graduated from IISERB in 2020)
  4. Subham Singh (Graduated from IISERB in 2020)
  5. Ritesh Kumar Singh (Graduated from IISERB in 2020)
  6. Sujeet Pani (Graduated from IISERB in 2021, Currently Graduate Student at the Center for Quantum Information and Control, University of New Mexico)
  7. Swayangprabha Shaw
  8. Sudhan Bhadade (Graduated from IISERB in 2022, Currently Graduate Student at the Center for Quantum Information and Control, University of New Mexico)
  9. Jemish Naliyapara (Graduated from IISERB in 2023)
  10. Dershik Ayyathan (Graduated from IISERB in 2023, Currently Graduate Student at the Department of Physics, The Technical University of Munich)

Contact

Dr. Phani Kumar P.

Assistant Professor

Department of Physics

IISER Bhopal


Office:

Room No. 3, Academic Building - I

Bhauri, Bhopal - 462066

Phone: +91 755 669 1241

Email: phani@iiserb.ac.in

Location