Entanglement, captures the degree of inseparability of quantum systems, turns out to be the resource exhibiting “quantum advantage” in various quantum information processing tasks like teleportation, dense coding, entanglement-based quantum cryptography and the detection of quantum phase transitions, to name a few. I will first discuss the violations of Bell inequality for two-mode continuous-variable states of light (Gaussian and non-Gaussian) both in the presence and absence of noise, thereby characterizing nonclassical quantum correlations in a device-independent manner. For Gaussian multimode states, I will present a closed-form expression of genuine entanglement (GME). In both cases, I will show how photon addition and subtraction lead to the enhancement of the nonclassical property under investigation. I will also discuss about novel phenomena observed in the dynamics of a quantum spin chain, known as dynamical quantum phase transition (DQPT) through the lens of quantum information theory and show genuine entanglement to be a sufficient criterion to indicate a DQPT.
I am Saptarshi Roy, senior research fellow at the Harish Chandra Research Institute (HRI), Allahabad, India. I did my BSc (Hons.) in Physics from Jadavpur University, Kolkata. I did MSc in Physics from HRI under the Homi Bhabha National Institute, and am pursuing a Ph. D. in physics from the same institute. I work on quantum information theory with my major research directions being quantum optics, quantum communications, and the interface between quantum information and many body physics.
Seminar by the NYU-ECNU Institute of Physics at NYU Shanghai