CMSP Seminar at ICTP Stasi Seminar Room Tuesday 2 August at 11.30 - D. SADHUKHAN

[Condensed Matter Section]

Condensed Matter and Statistical Physics Seminar
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Tuesday, 2 August at 11.30 a.m.
Luigi Stasi Seminar Room, first floor, Leonardo Building

Debasis SADHUKHAN
Quantum Information and Computation Group
Physics Division, Harish-Chandra Research Institute
Allahabad, India

Title: Statics and Dynamical Quantum Correlations in Inhomogeneous
Transverse Field XY Model

Abstract:
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Homogeneous quantum system is very rare in nature due to decoherence,
thermal fluctuations, impurities, etc. Hence, inhomogeneous quantum 
many-body
systems form a more practical ground to implement quantum information 
protocols.
Equilibrium and non-equilibrium dynamics of quantum correlations in 
homogeneous
spin systems is well studied in literature. We have investigated the 
static and dynamical
patterns of entanglement in an anisotropic XY model with an alternating 
transverse
magnetic field. Apart from the antiferromagnetic and paramagnetic 
phases, the model
possesses a dimer phase which is not present in the homogeneous 
transverse field XY
model. At zero temperature, we find that the first derivative of 
bipartite entanglement
can detect all the three phases. Next, we introduce more inhomogeneity 
in the transverse
field in the same system and study the behaviour of entanglement in a 
random-field
quantum XY model under quenched disorder. I will show that the quantum 
discord length
is significantly enhanced by the introduction of disorder while 
entanglement length show
no significant enhancement.