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Antonio M. García-García
Tenured Associate Professor 
School of Physics
Shanghai Jiao Tong University
Shanghai Center For Complex Physics
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 RESUME
TOP PAPERS
LECTURES
TALKS
PUBLICATIONS
TEACHING

RESEARCH
PEOPLE
SUPERCONDUCTIVITY, MESOSCOPIC PHYSICS, AdS/CFT, QUANTUM GRAVITY 
 POSTDOCS


I am a theoretical physicist with a broad spectrum of research interests that include low dimensional superconducitvity, strongly correlated systems and mesoscopic physics with a special emphasis on novel two dimensional superconducting materials, and holographic dualities. Two topic of current interests are the nano-engineering of novel disordered two dimensional superconductors and the physics of the SYK model and its quantum gravity dual: Jackiw-Teitelboim gravity.
SUPERCONDUCTIVITY BY DESIGN
 NOVEL FORMS OF  QUANTUM MATTER
Recent technological advances in both growth and measurement of nano/hetero structures  have put the basis to study quantitatively nanoscale superconductivity. One particular area of interest is the identification of materialsphysical mechanisms and geometrical arrangements which lead to an enhancement of superconductivity in the nanoscale. Examples of interest include copper oxides heterostructures, LAO/STO and FeSe/STO interfaces and granular conventional superconductors. Together with James Mayoh and Aurelio Bermudez, I have proposed a novel method  to engineer more robust superconductivity by controlled nano-granularity and also investigated the role of the substrate in the enhancement of superconductivity in thin films. Together with Lara Benfatto et al. we have recently verifed that coherence effects related to nano-granularity help explain the enhancement of Tc observed in granular Al. Currently we are investigating whether similar mechanism could enhance superconductivity in novel engineered two dimensional superconductors such as FeSe/STO.
The ground state of all forms of superconductivity is a superposition of dimers, either spin-singlet or spin-triplet, which for sufficiently low temperature condensate. However the Efimov effect, that predicts the existence of bound states of three distinguishable particles even in the limit of no bound states for two particles, suggests the possibility of a richer phenomenology. Together with Pascal Naidon in Riken and Shimpei Endo in Paris,  we have found that Efimov physics can induce novel forms of stable  quantum matter, more specifically a trimer Fermi liquid. Topologically non trivial quantum matter also offers a promising arena to discover non-conventional superconductors.  We have recently studied the distinctive features of a supercurrent in a dissipative topological Josephson junction. Currently we are working on condensed matter realisations of Efimov physics and its potential to realise novel forms of superconductivity.


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It is now possible to control and measure the size and shape of a superconducting nanograin.  This paves the way for a quantitative understanding of nanoscale superconductivity. Figure from Nature Materials, 9, 550 (2010). It is possible to substantially enhance the critical temperature of bulk superconductors  by granular nanoengineering.  Figure from Phys. Rev. B 90, 134513 (2014) for grain size ~5nm and, from top to bottom,  FCC, BCC and cubic packings.


HOLOGRAPHIC DUALITIES & QUANTUM GRAVITY
 OUT OF EQUILIBRIUM DYNAMIC & THERMALIZATION
The AdS/CFT correspondence, also referred to as the holographic principle, is arguably he most important theoretical development in high energy physics of the last decade. It conjectures that certain strongly coupled field theories are dual of weakly coupled gravity theories in a different dimension. The application of the holographic duality in condensed matter systems is rapidly emerging as a forefront research field. Problems of special interest are those in which some sort of universality is expected. For instance, together with Hong Liu and P. Chesler, I have reported novel aspects of the physics of out of equilibrium defect generation by holography techniques and scaling ideas. More recently I am working with Jac Verbaarschot and other collaborators on the physics of the Sachdev-Ye-Kitaev which has attracted a lot of recent attention as a toy model of holography with a (quantum) gravity dual: Jackiw-Teitelboim gravity.

The conditions leading to thermalization in a closed system after a quatum quench is being intensively investigated in recent years. I am interested on the role of spatial inhomogeneities and topological fluctuations (vortices and phase slips) in this process.  In two dimension this is closely related to the physics of the Kosterlitz Thouless transition out of equilibrium. I have recently investigated this problem by studying  the out of equilibirum dynamics resulting from a quench in the spatial dimensionality of a strongly correlated system. Currently I am also interested in the study of transport properties of strongly correlated systems, especially universal aspects such as the existence of dynamical bounds, in collaboration with David Berenstein, or  generic features, in collaboration with Lea Santos, of the out of equilibrium motion which could provide helpful insight on the conditions for thermalisation. 

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Time evolution of the order parameter of a two dimensional holographic superlfuid, from PRX 5 021015 (2015)  , as it is cooled from the disordered to the ordered phase.  According to the Kibble-Zurek mechnanism the number vortices, generated at tfreeze, scale with the quench speed. We have found that only at a later time teq vortices are formed and that the scaling with the quench speed breaks down for sufficiently fast quenches.





                                          
            Vaios Ziogas                Shuang Wu           Salomon Zacarias     

    PhD STUDENTS

                                                                                                                                         
                             Jie Ping Zheng                                Bo Fan  
COLLABORATORS

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Klaus Kern
Stuttgart
Sangita Bose
Bombay
Miguel Cazalilla
Tsinghua Taipei
Wang Jiao
Xiamen
emi masa
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Emilio Cuevas
Murcia
Masaki Tezuka
Kyoto
Marcos Rigol
Pennsylvania
Diego Rodriguez
Oviedo

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a
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Emil Yuzbashyan
Rutgers
Boris Altshuler
Columbia
Pedro Sacramento
Lisbon
Ehsan Khatami
Georgetown

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Klaus Richter
Regensburg
Juan Urbina
Regensburg
Pascal Naidon
Riken, Saitama
Armando Relaño        Madrid

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Jac Verbaarschot
Stony Brook
James Osborn
Argonne
Shinsuke Nishigaki Shimane, Matsue

Jorge Hirsch
UAM, Mexico DF

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benson
Sebastian Franco
Durham
Ivan Brihuega
UAM, Madrid
Jorge Santos
Stanford
Benson Way
Cambridge




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Paul Chesler
Harvard

Hong Liu
MIT

David Berenstein
UC Santa Barbara
Shimpei Endo
Paris


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guy
uwe
martin
Nimrod Bachar
Geneve University

Guy Deutscher
Tel-Aviv

Uwe S. Pracht
Stuttgart U.

Martin Dressel
Stuttgart U.

aurelio
Lara
lea
claudio
Aurelio Bermudez
Leiden University

 Lara Benfatto 
laSapienza, Rome

      Lea Santos
Yeshiva U.  NYC

Claudio Castellani
laSapienza, Rome

Ribeiro
Hia
                              Qing
James
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Pedro Ribeiro
Lisboa University

Hai-Qing Zhang
Utrecht University
James Mayoh
Southampton U
Hua Bi Zeng
Bohai University

Carmen Verdu
Columbia
Miguel Ugeda
DIPC
Zhi-Xun Shen
Stanford
 José Ignacio Pascual
DIPC