Doctoral theses
Current Record: 30 of 168
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Identifier |
000427564 |
Title |
Ultrafast spin-charge quantum dynamics in strongly correlated systems |
Alternative Title |
Υπερταχεία κβαντική δυναμική σπιν-φορτίου σε ισχυρά συσχετιζόμενα συστήματα |
Author
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Λίγγος, Παναγιώτης
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Thesis advisor
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Περάκης, Ηλίας
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Abstract |
In this thesis we investigate the possible role in a non-equilibrium phase transition of
non-thermal fs dynamics of electronic, magnetic, and lattice coupled degrees of freedom
within a theoretical framework based on Hubbard operators that treats the magnetic exchange interaction at the microscopic level. We propose a possible mechanism for photoinduced phase transition
based on the interplay between a quasi-instantaneous electronic/magnetic pathway and
a delayed lattice pathway. In particular, we discuss the possibility that the excitation of
composite fermion itinerant quasi-particles dressed by spin fluctuations triggers quasi-
instantaneously an insulator to metal and AFM to FM phase transition by providing
time-dependent numerical results based on real-space models by solving the quantum kinetic equations of motion. We examine in the role of spin fluctuations driven by photo-carrier populations
that interact with a deformable spin and lattice medium. We also discuss the role of the quasi-particle energy bands, modified by fs laser excitation, which arise
from electron-magnon coupling and the strong Hund’s rule local interaction.
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Language |
English |
Subject |
Insulator-metal transition |
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Photoinduced spin dynamics |
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Δυναμική σπιν φεμτοδευτερολέπτων |
Issue date |
2020-01-20 |
Collection
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School/Department--School of Sciences and Engineering--Department of Physics--Doctoral theses
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Type of Work--Doctoral theses
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Permanent Link |
https://elocus.lib.uoc.gr//dlib/2/2/6/metadata-dlib-1579509989-988428-14668.tkl
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Views |
684 |