The origin of this anomalous metallic state is thought to be a liquid-like state in which magnetic flux lines (Fig. 1 left) that permeate into the superconductor move around due to quantum fluctuations.However, this prediction has not been corroborated because many previous experiments on two-dimensional superconductors have used electrical resistivity measurements that analyze the voltage action to current, making it tough to identify between voltage signals stemming from the motion of magnetic flux lines and those originating from the scattering of normal-conducting electrons.A research team led by Assistant Professor Koichiro Ienaga and Professor Satoshi Okuma of the Department of Physics, School of Science at Tokyo Tech reported in Physical Review Letters in 2020 that quantum movement of magnetic flux lines takes place in an anomalous metal state by using the thermoelectric result, in which voltage is generated with regard to heat flow (temperature level gradient) rather than current.However, to even more clarify the origin of the anomalous metallic state, it is essential to elucidate the mechanism by which the superconducting state is destroyed by quantum fluctuation and shifts to the regular (insulating) state. It is 10 nanometers thick (one nanometer is one billionth of a meter) and assures to have the change effects particular of two-dimensional systems.Since change signals can not be found by electrical resistivity measurements since they are buried in the signal of normal-conducting electron scattering, we performed thermoelectric effect measurements, which can discover two types of variations: (1) superconducting fluctuations (variations in the amplitude of superconductivity) and (2) magnetic flux line motion (changes in the phase of superconductivity). That exposes that superconducting fluctuations endure not only in the liquid region of the magnetic flux (dark red region in Fig. 2), where superconducting phase changes are more noticable, however also over a wide temperature-magnetic field region farther outwards that is considered to be the normal-state region, where superconductivity is ruined (the high-temperature and high-magnetic field region above the upper convex solid line in Fig. 2). It is regular for thermal fluctuations to take place, but near outright absolutely no, quantum fluctuations take place based on the quantum mechanical uncertainty principle.Thermoelectric effect: A result of exchanging thermal and electrical energy. The quantum vital point is the phase shift point where a quantum stage transitions take place and where quantum fluctuations are strongest.Amorphous structure: A structure of product in which atoms are organized in an irregular manner and which has no crystalline structure.Quantum condensed state: A state in which a large number of particles fall into the most affordable energy state and behave as a particular macroscopic wave.
It is 10 nanometers thick (one nanometer is one billionth of a meter) and promises to have the fluctuation impacts characteristic of two-dimensional systems.Since fluctuation signals can not be found by electrical resistivity measurements since they are buried in the signal of normal-conducting electron scattering, we carried out thermoelectric effect measurements, which can spot two types of variations: (1) superconducting variations (variations in the amplitude of superconductivity) and (2) magnetic flux line motion (variations in the stage of superconductivity). That exposes that superconducting variations survive not only in the liquid area of the magnetic flux (dark red region in Fig. 2), where superconducting phase variations are more noticable, but likewise over a broad temperature-magnetic field region farther outwards that is considered to be the normal-state area, where superconductivity is damaged (the high-magnetic and high-temperature field region above the upper convex solid line in Fig. 2). It is regular for thermal changes to occur, however near absolute zero, quantum fluctuations occur based on the quantum mechanical unpredictability principle.Thermoelectric impact: An impact of exchanging thermal and electrical energy.
