Photoinduced phase transitions

Last updated

Photoinduced phase transition is a technique used in solid-state physics. It is a process to the nonequilibrium phases generated from an equilibrium by shining on high energy photons, and the nonequilibrium phase is a macroscopic excited domain that has new structural and electronic orders quite different from the starting ground state (equilibrium phase). [1] [2]

Related Research Articles

<span class="mw-page-title-main">Phase (matter)</span> Region of uniform physical properties

In the physical sciences, a phase is a region of space, throughout which all physical properties of a material are essentially uniform. Examples of physical properties include density, index of refraction, magnetization and chemical composition. A simple description is that a phase is a region of material that is chemically uniform, physically distinct, and (often) mechanically separable. In a system consisting of ice and water in a glass jar, the ice cubes are one phase, the water is a second phase, and the humid air is a third phase over the ice and water. The glass of the jar is another separate phase.

<span class="mw-page-title-main">Phase transition</span> Physical process of transition between basic states of matter

In chemistry, thermodynamics, and other related fields, a phase transition is the physical process of transition between one state of a medium and another. Commonly the term is used to refer to changes among the basic states of matter: solid, liquid, and gas, and in rare cases, plasma. A phase of a thermodynamic system and the states of matter have uniform physical properties. During a phase transition of a given medium, certain properties of the medium change as a result of the change of external conditions, such as temperature or pressure. This can be a discontinuous change; for example, a liquid may become gas upon heating to its boiling point, resulting in an abrupt change in volume. The identification of the external conditions at which a transformation occurs defines the phase transition point.

<span class="mw-page-title-main">Phase diagram</span> Chart used to show conditions at which physical phases of a substance occur

A phase diagram in physical chemistry, engineering, mineralogy, and materials science is a type of chart used to show conditions at which thermodynamically distinct phases occur and coexist at equilibrium.

<span class="mw-page-title-main">Photoluminescence</span> Light emission from substances after they absorb photons

Photoluminescence is light emission from any form of matter after the absorption of photons. It is one of many forms of luminescence and is initiated by photoexcitation, hence the prefix photo-. Following excitation, various relaxation processes typically occur in which other photons are re-radiated. Time periods between absorption and emission may vary: ranging from short femtosecond-regime for emission involving free-carrier plasma in inorganic semiconductors up to milliseconds for phosphoresence processes in molecular systems; and under special circumstances delay of emission may even span to minutes or hours.

The fluctuation theorem (FT), which originated from statistical mechanics, deals with the relative probability that the entropy of a system which is currently away from thermodynamic equilibrium will increase or decrease over a given amount of time. While the second law of thermodynamics predicts that the entropy of an isolated system should tend to increase until it reaches equilibrium, it became apparent after the discovery of statistical mechanics that the second law is only a statistical one, suggesting that there should always be some nonzero probability that the entropy of an isolated system might spontaneously decrease; the fluctuation theorem precisely quantifies this probability.

<span class="mw-page-title-main">Non-equilibrium thermodynamics</span> Branch of thermodynamics

Non-equilibrium thermodynamics is a branch of thermodynamics that deals with physical systems that are not in thermodynamic equilibrium but can be described in terms of macroscopic quantities that represent an extrapolation of the variables used to specify the system in thermodynamic equilibrium. Non-equilibrium thermodynamics is concerned with transport processes and with the rates of chemical reactions.

Synergetics is an interdisciplinary science explaining the formation and self-organization of patterns and structures in open systems far from thermodynamic equilibrium. It is founded by Hermann Haken, inspired by the laser theory. Haken's interpretation of the laser principles as self-organization of non-equilibrium systems paved the way at the end of the 1960s to the development of synergetics. One of his successful popular books is Erfolgsgeheimnisse der Natur, translated into English as The Science of Structure: Synergetics.

A quantum critical point is a point in the phase diagram of a material where a continuous phase transition takes place at absolute zero. A quantum critical point is typically achieved by a continuous suppression of a nonzero temperature phase transition to zero temperature by the application of a pressure, field, or through doping. Conventional phase transitions occur at nonzero temperature when the growth of random thermal fluctuations leads to a change in the physical state of a system. Condensed matter physics research over the past few decades has revealed a new class of phase transitions called quantum phase transitions which take place at absolute zero. In the absence of the thermal fluctuations which trigger conventional phase transitions, quantum phase transitions are driven by the zero point quantum fluctuations associated with Heisenberg's uncertainty principle.

<span class="mw-page-title-main">Joel Lebowitz</span> American mathematical physicist

Joel Louis Lebowitz is a mathematical physicist widely acknowledged for his outstanding contributions to statistical physics, statistical mechanics and many other fields of Mathematics and Physics.

<span class="mw-page-title-main">Alexander Kuzemsky</span> Russian physicist

Alexander Leonidovich Kuzemsky is a Russian theoretical physicist.

Alexander Zakharovich Patashinski was a Soviet and Russian physicist. He is a professor for Materials Research Scientist and professor at Northwestern University in Evanston, Illinois.

Dmitry Nikolayevich Zubarev was a Soviet and Russian theoretical physicist known for his contributions to statistical mechanics, non-equilibrium thermodynamics, plasma physics, theory of turbulence, and to the development of the double-time Green function's formalism.

The glass–liquid transition, or glass transition, is the gradual and reversible transition in amorphous materials from a hard and relatively brittle "glassy" state into a viscous or rubbery state as the temperature is increased. An amorphous solid that exhibits a glass transition is called a glass. The reverse transition, achieved by supercooling a viscous liquid into the glass state, is called vitrification.

<span class="mw-page-title-main">Gavin E. Crooks</span> English chemist

Gavin E. Crooks is an English chemist currently researching in the USA. He is known for his work on non-equilibrium thermodynamics and statistical mechanics. He discovered the Crooks fluctuation theorem, a general statement about the free energy difference between the initial and final states of a non-equilibrium transformation.

Ezechiel Godert David "Eddie" Cohen was a Dutch-American physicist and Professor Emeritus at The Rockefeller University. He is widely recognised for his contributions to statistical physics. In 2004 Cohen was awarded the Boltzmann Medal, jointly with Prof. H. Eugene Stanley. Cohen's citation read "For his fundamental contributions to nonequilibrium statistical mechanics, including the development of a theory of transport phenomena in dense gases, and the characterization of measures and fluctuations in nonequilibrium stationary states."

A hidden state of matter is a state of matter which cannot be reached under ergodic conditions, and is therefore distinct from known thermodynamic phases of the material. Examples exist in condensed matter systems, and are typically reached by the non-ergodic conditions created through laser photo excitation. Short-lived hidden states of matter have also been reported in crystals using lasers. Recently a persistent hidden state was discovered in a crystal of Tantalum(IV) sulfide (TaS2), where the state is stable at low temperatures. A hidden state of matter is not to be confused with hidden order, which exists in equilibrium, but is not immediately apparent or easily observed.

<span class="mw-page-title-main">Bianconi–Barabási model</span>

The Bianconi–Barabási model is a model in network science that explains the growth of complex evolving networks. This model can explain that nodes with different characteristics acquire links at different rates. It predicts that a node's growth depends on its fitness and can calculate the degree distribution. The Bianconi–Barabási model is named after its inventors Ginestra Bianconi and Albert-László Barabási. This model is a variant of the Barabási–Albert model. The model can be mapped to a Bose gas and this mapping can predict a topological phase transition between a "rich-get-richer" phase and a "winner-takes-all" phase.

Gholam Ali Mansoori, G. Ali Mansoori also known as "GA Mansoori" is an Iranian-American scientist known for his research within energy, nanotechnology and thermodynamics. He is a professor at the Departments of Bioengineering, Chemical Engineering and also Physics at University of Illinois at Chicago.

Bose–Einstein condensation of polaritons is a growing field in semiconductor optics research, which exhibits spontaneous coherence similar to a laser, but through a different mechanism. A continuous transition from polariton condensation to lasing can be made similar to that of the crossover from a Bose–Einstein condensate to a BCS state in the context of Fermi gases. Polariton condensation is sometimes called “lasing without inversion”.

Sanjay Puri is an Indian statistical physicist and a senior professor at the School of Physical Sciences of Jawaharlal Nehru University. Known for his research on non-linear dynamics, Puri is an elected fellow of the Indian Academy of Sciences and the Indian National Science Academy. The Council of Scientific and Industrial Research, the apex agency of the Government of India for scientific research, awarded him the Shanti Swarup Bhatnagar Prize for Science and Technology, one of the highest Indian science awards, for his contributions to physical sciences in 2006.

References

  1. Nasu, K. (2004). Photoinduced Phase Transitions. World Scientific Publishing Co. Pte. Ltd. ISBN   981-238-763-3
  2. Nicholson CW, Lücke A, Schmidt WG, Puppin M, Rettig L, Ernstorfer R, Wolf M. Beyond the molecular movie: Dynamics of bands and bonds during a photoinduced phase transition. Science. 2018 Nov 16;362(6416):821-825. doi : 10.1126/science.aar4183 PMID   30442808