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Theory of Ultracold Atoms2014 PhD TopicsUltracold atoms near
Feshbach resonances are stronglycorrelated many-body systems,
supporting novel exotic statesof matter that may universally exist
in new functionalmaterials of high-Tcsuperconductors and mysterious
cosmicobjects such as neutron stars. The understanding of
theseexotic states - being a long-sought theoretical challenge -
is
the subject of our PhD topics.
See: http://www.swinbune.edu.au/feis/caous/
SUT PHYSICS: INTERNATIONAL TOP 100
TOP 2 IN AUSTRALIA (Jiao-Tong List, 2013)
Swinburne University of Technology
Centre for Quantum and Optical Science
Nature Physics 3, 469 (2007). This is the first
published evidence for universality, comparing
different strongly interacting Fermi gases.
Strong-coupling Diagrammatic Theory
Strongly correlated atomic gases near Feshbach resonances are
notoriously difficultto understand, because of the absence of a
small interaction parameter. Thetraditional perturbative expansion
in terms of the interaction parameter is not reliable,while
ab-initio Monte Carlo simulations often suffer from the Fermi sign
problem.Here, we aim to develop quantitative strong-coupling
diagrammatic theories and toprovide theoretical guidance to
experiments at Swinburne University.
Quantitative strong-coupling theory of ultracold Fermi and Bose
gases
Superfluid density of unitary Fermi and Bose gasesDensity and
spin density dynamic structure factor of a unitary Fermi gas
Phys. Rev. Lett. 102, 160401 (2009); 104, 240407
(2010). Review in Physics Reports 524, 37 (2013).
Quantum Virial Expansion Theory
Quantum virial expansion is an entirely new direction to handle
strong correlations,which is extremely useful at high temperatures.
It allows a controllable expansion tobe worked out even in three
dimensions, in terms of a small parameter - the fugacity.It
provides an elegant way to bridge the few-body and the many-body
worlds. Ourspecific schemes in this topic include:
Four-particle solutions and the fourth virial
coefficientHigh-order expansion of the single-particle spectral
function of a unitary Fermi gasTrimer signature in the dynamic
structure factor of a unitary Bose gas
Superfluidity in Flat Land and One Dimension
Superfluidity in low-dimensional systems exhibits remarkable
features, due to strongphase fluctuations. In the flat land of two
dimensions, the onset of superfluidity isgoverned by the so-called
Berezinskii-Kosterlitz-Thouless (BKT) mechanism. In onedimension,
exotic inhomogeneous superfluid known as
Fulde-Ferrell-Larkin-Ovchinnikov (FFLO) phase may appear.
High-precision measurements in low-dimensional strongly interacting
Fermi gases are now under way at SwinburneUniversity. In this
topic, we aim to study:
Thermodynamics of strongly interacting Fermi and Bose gases in
flat landFirst and second sound across the BKT transition
Dimensional crossover from 3D to 2D, and to 1D
Ultracold Atoms with Synthetic Gauge Field
The latest development in ultracold atoms is the engineering of
a synthetic gaugefield, which leads to the (spin-orbit) coupling
between the spin and the orbital degreesof freedom of the atoms.
This creates a new frontier that is endowed with a
stronginterdisciplinary character and a close connection to other
research fields, includingcondensed matter physics, quantum
computation and astrophysics. Our researchfocuses on topological
fermionic superfluids and possible exotic bosonic superfluidswith
nontrivial spin-textures.
Topological (inhomogeneous) superfluids with Raman
couplingExotic superfluids in trapped Bose-Einstein condensates
with spin-orbit couplingLandau two-fluid hydrodynamics in
spin-orbit coupled quantum gases
Deadline: May 31, 2014Two full scholarships available (A$24,653
pa 3.5y)Apply to: [email protected]
Phys. Rev. Lett. 108, 010402 (2012); 107,
195304 (2011); 110, 020401 (2013). Exotic
superfluids in spin-orbit coupled atomic gases.
Phys. Rev. Lett. 98, 070403 (2007); Phys. Rev.
A 76, 043605 (2007). FFLO superfluidity in 1D.
Supervisors: Assoc. Prof. Xia-Ji Liu and Hui Hu
