Nir Bar-Gill
Krill Prize 2017
Hebrew University
Dr. Nir Bar-Gill
Title: Quantum science and applications with diamond
My research aims to create a new platform for both fundamental studies in quantum science and interdisciplinary ap- plications. Specifically, I am researching the nitrogen-vacancy (NV) color center in diamond, which can serve as a building block for quantum information processing, quantum simulation and quantum sensing. My research program focuses on these three aspects of the diamond-NV platform, which I detail below.
In the context of quantum information building blocks, NV centers in diamond have been recently identified as unique atom-like quantum spins embedded in a solid-state structure, that have remarkable optical and microwave control. Over the past few years, these unique properties have propelled the field forward tremendously, resulting in significant achievements, including our demonstration of record-long coherence times approaching 1 second [7]. These results position NVs as leading candidates for various quantum information applications. We are extending the current state- of-the-art in this context through optimized, advanced control sequences [3]. Based on this, we aim at reaching the regime of fast coherent interactions in an NV ensemble (compared to the coherence time), which would allow the cre- ation of highly entangled states, such as spin-squeezed states, relevant for quantum memories and quantum metrology.
Based on these NV quantum building blocks described above, we are advancing a novel architecture for scalable quan- tum simulators in diamond. We are proceeding at the fore-front of this field, progressing toward novel hybrid ap- proaches connecting disparate physical realizations (including solid-state, photonic and atomic). In our case, we are developing quantum spin networks with a large number of individually addressed spins (optically), coupled through superconducting structures. This work could lead to scalable, universal quantum simulation and quantum computing, addressing open research questions such as frustrated spin systems, surface codes, dissipative quantum dynamics of many-body spin systems and effects of disorder on quantum and topological phases.
Finally, I am exploring the direction of using diamond devices as quantum sensors and specifically magnetic sensors, and applying this new technology to various fields of science, including physics, biology and earth sciences. For example, I am collaborating with Dr. Ron Shaar from the Institute for Earth Sciences, studying magnetic signatures of various minerals and rock samples, to gain insight into the physics of the underlying magnetization process, and to extract otherwise unavailable climactic data over a large timespan (tens of thousands of years), relevant for open ques- tions in global warming.
I am also collaborating with Prof. Stefan Hell on creating a novel two-beam super-resolution NV microscope (based on his pioneering technique, STED – STimulated Emission Depletion microscopy), which will allow sensitive pump-probe measurements on the nanoscale. This approach could reveal new information regarding magnetic and spin dynamics in condensed matter systems, e.g. measurements of the spin susceptibility of graphene and various Van-der-Walls mate- rials (including topological insulators).
Moreover, I am engaged in developing a nanoscale MRI (Magnetic Resonance Imaging) device, which could complement existing technologies, and provide a cheap, portable and yet sensitive alternative, relevant for a variety of medical sce- narios, and for situations in which traditional MRI machines are not available, e.g. third-world countries and field treat- ments.