The polaron phenomenon is commonly observed in low-dimensional semiconductor materials and is known to have unique effects on conductive material properties.Furthermore,the phonon dragging effect,which leads to the po...The polaron phenomenon is commonly observed in low-dimensional semiconductor materials and is known to have unique effects on conductive material properties.Furthermore,the phonon dragging effect,which leads to the polaron energy level,is less than the electron energy level.A decay magnetic field also affects the polaron effect,which causes polaron energy level changes.We demonstrate the unique electron-phonon coupling properties of this polaron using numerical calculations.Our findings have strong implications for theories of polaron properties and provide compelling evidence for a semiconductor device that industrial manufacturers use for new lowdimensional materials.展开更多
By using variational method of Pekar type, we have studied the energy levels of strong coupling magnetopolaron in disk shape quantum dot(QD) and quantum well(QW). Our results show that, with the increasing magnetic f...By using variational method of Pekar type, we have studied the energy levels of strong coupling magnetopolaron in disk shape quantum dot(QD) and quantum well(QW). Our results show that, with the increasing magnetic field and confinement strength, the magnetopolaron binding energy of QD and QW in the ground state and in the excited state is enhanced. The limiting results of bulk type and strict two dimensional type are obtained.展开更多
With the use of variational method of Pekar type, this paper studied the energy levels of magnetopolaron in quantum wire with strong electron phonon interaction. The magnetopolaron binding energy in the ground state a...With the use of variational method of Pekar type, this paper studied the energy levels of magnetopolaron in quantum wire with strong electron phonon interaction. The magnetopolaron binding energy in the ground state and in the excited state, as well as the resonance frequency of magnetopolaron were calculated. Their dependence on the cyclotron frequency and the confinement strength of quantum wire was depicted. The limiting case of bulk type and strict two dimensional type was discussed.展开更多
By using the variational method of Pekar type, the ground state and the first excited state of the strong coupling magnetopolaron in cylinder shape quantum dot are considered. The results show that, with the increasi...By using the variational method of Pekar type, the ground state and the first excited state of the strong coupling magnetopolaron in cylinder shape quantum dot are considered. The results show that, with the increasing cyclotron frequency and the confinement strength, the magnetopolaron binding energies in both the ground state and the excited state, and the resonance frequency of magnetopolaron are enhanced. The limiting case of the bulk and strict one dimensional type is also discussed.展开更多
The cyclotron mass of magnetopolarons in wurtzite InxGa1-xN/GaN quantum well is studied in the presence of an external magnetic field by using the Larsen perturbation method. The effects of the built-in electric field...The cyclotron mass of magnetopolarons in wurtzite InxGa1-xN/GaN quantum well is studied in the presence of an external magnetic field by using the Larsen perturbation method. The effects of the built-in electric field and different phonon modes including interface, confined and half-space phonon modes are considered in our calculation. The results for a zinc-blende quantum well are also given for comparison. It is found that the main contribution to the transition energy comes from half-space and interface phonon modes when the well width is very small while the confined modes play a more important role in a wider well due to the location of the electron wave function. As the well width increases, the cyclotron mass of magnetopolarons first increases to a maximum and then decreases either with or without the built-in electric field in the wurtzite structure and the built-in electric field slightly reduces the cyclotron mass. The variation of cyclotron mass in a zinc-blende structure is similar to that in a wurtzite structure. With the increase of external magnetic field, the cyclotron mass of polarons almost linearly increases. The cyclotron frequency of magnetopolarons is also discussed.展开更多
The cyclotron resonance of magnetopolaron in quantum well wires (QWWs) have been studied with the use of variational solutions to the effective mass equation. The results show that both the abso- lute value of the ele...The cyclotron resonance of magnetopolaron in quantum well wires (QWWs) have been studied with the use of variational solutions to the effective mass equation. The results show that both the abso- lute value of the electron-phonon interaction energy and the cyclotron resonance frequency de- crease with the increase of the sizes of QWWs, and also that the cyclotron resonance frequency in- creases with the external magnetic field.展开更多
A theory of triple magnetopolarons in an isolated quantum well in a strong magnetic field was developed. We study the behavior of the magnetooptical absorption peaks corresponding to the transitions of an electron at ...A theory of triple magnetopolarons in an isolated quantum well in a strong magnetic field was developed. We study the behavior of the magnetooptical absorption peaks corresponding to the transitions of an electron at the Landau level with quantum numbers n ≥ 2. For n = 2 at the point of equality of cyclotron frequency and the frequency of optical phonon (LO), there is a cross of three terms of the electron-phonon system (the electron at the Landau level n = 2, the electron at n = 1, and the optical phonon and electron at n = 0 and two phonons), considered as a function of the cyclotron frequency. Interaction with phonons takes off the degeneracy of the terms and leads to three disjoint branches of the electron-phonon spectrum. The theory predicts that in the resonant magnetic field, the peak of magnetooptical absorption splits into three peaks, the intensity and position of which are dependent in a complex way on the magnitude of the magnetic field and the constant of the electron-phonon coupling.展开更多
Magnetic field and temperature dependence of the properties of the ground state of the strong-coupling bound magnetopolaron in quantum rods （QRs） with hydrogenic impurity is studied by means of the Huybrechts- Lee-L...Magnetic field and temperature dependence of the properties of the ground state of the strong-coupling bound magnetopolaron in quantum rods （QRs） with hydrogenic impurity is studied by means of the Huybrechts- Lee-Low-Pines transformation method and the quantum statistical theory. The expressions for the ground-state energy and the mean number ofphonons of the magnetopolaron are derived. Results of the numerical calculations show that the bound state of the magnetopolaron cannot be formed when the value of the aspect ratio of the QR, the dielectric constant ratio, the electron-phonon coupling strength or the temperature parameter is small. The larger the deviation of the value of aspect ratio e′ from 1 is, the more it is unfavorable to the stability of the ground state of the magnetopolaron. When the magnetopolaron is in the bound state, the absolute value of its ground-state energy and its mean number ofphonons increase with an increase of the dielectric constant ratio and confinement strength of QRs, but decrease with an increase in the cyclotron frequency of the external magnetic field and the temperature. The absolute value of the ground-state energy and the mean number of phonons of the magnetopolaron decrease with decreasing e′ when e′ 〈 1, but decrease with increasing e′ when e′ 〉 1. They get the maximum value at e′=1.展开更多
The superconductivity in (NbTa)<sub>1-X</sub>(HfZrTi)<sub>X</sub> high-entropy alloy is analyzed using the theory of strong-coupled superconductor. It is concluded that (NbTa)<sub>1-X<...The superconductivity in (NbTa)<sub>1-X</sub>(HfZrTi)<sub>X</sub> high-entropy alloy is analyzed using the theory of strong-coupled superconductor. It is concluded that (NbTa)<sub>1-X</sub>(HfZrTi)<sub>X </sub>is a strong coupled superconductor. The variation in the superconducting transition temperature from 7.9 K to 4.6 K as x increases from 0.2 to 0.84 arises because of the decrease in electronic band width due to localization and broadening of the band. It is suggested that the decrease in electronic band width is due to crystalline randomness which gives rise to the mobility edge.展开更多
基金supported by the National Natural Science Foundation of China(12164032 and 11964026)the Natural Science Foundation of Inner Mongolia(No.2019MS01010,2022MS01014)+1 种基金Doctor Research Start-up Fund of Inner Mongolia Minzu University(BS625)Scientific Research Projects in Colleges and Universities in Inner Mongolia(No.NJZZ19145)
文摘The polaron phenomenon is commonly observed in low-dimensional semiconductor materials and is known to have unique effects on conductive material properties.Furthermore,the phonon dragging effect,which leads to the polaron energy level,is less than the electron energy level.A decay magnetic field also affects the polaron effect,which causes polaron energy level changes.We demonstrate the unique electron-phonon coupling properties of this polaron using numerical calculations.Our findings have strong implications for theories of polaron properties and provide compelling evidence for a semiconductor device that industrial manufacturers use for new lowdimensional materials.
文摘By using variational method of Pekar type, we have studied the energy levels of strong coupling magnetopolaron in disk shape quantum dot(QD) and quantum well(QW). Our results show that, with the increasing magnetic field and confinement strength, the magnetopolaron binding energy of QD and QW in the ground state and in the excited state is enhanced. The limiting results of bulk type and strict two dimensional type are obtained.
基金Science Foundation of Shanghai MunicipalCommission of Education(99QF5 5 ) Oneof us(S.Gu) also acknowledged the fi-nancial support of National Natural Sci-ence Foundation of China(No.197740 40 )
文摘With the use of variational method of Pekar type, this paper studied the energy levels of magnetopolaron in quantum wire with strong electron phonon interaction. The magnetopolaron binding energy in the ground state and in the excited state, as well as the resonance frequency of magnetopolaron were calculated. Their dependence on the cyclotron frequency and the confinement strength of quantum wire was depicted. The limiting case of bulk type and strict two dimensional type was discussed.
文摘By using the variational method of Pekar type, the ground state and the first excited state of the strong coupling magnetopolaron in cylinder shape quantum dot are considered. The results show that, with the increasing cyclotron frequency and the confinement strength, the magnetopolaron binding energies in both the ground state and the excited state, and the resonance frequency of magnetopolaron are enhanced. The limiting case of the bulk and strict one dimensional type is also discussed.
基金Project supported by the National Natural Science Foundation of China (Grant No. 10964007)the Natural Science Foundation of Inner Mongolia,China (Grant No. 2009MS0110)
文摘The cyclotron mass of magnetopolarons in wurtzite InxGa1-xN/GaN quantum well is studied in the presence of an external magnetic field by using the Larsen perturbation method. The effects of the built-in electric field and different phonon modes including interface, confined and half-space phonon modes are considered in our calculation. The results for a zinc-blende quantum well are also given for comparison. It is found that the main contribution to the transition energy comes from half-space and interface phonon modes when the well width is very small while the confined modes play a more important role in a wider well due to the location of the electron wave function. As the well width increases, the cyclotron mass of magnetopolarons first increases to a maximum and then decreases either with or without the built-in electric field in the wurtzite structure and the built-in electric field slightly reduces the cyclotron mass. The variation of cyclotron mass in a zinc-blende structure is similar to that in a wurtzite structure. With the increase of external magnetic field, the cyclotron mass of polarons almost linearly increases. The cyclotron frequency of magnetopolarons is also discussed.
文摘The cyclotron resonance of magnetopolaron in quantum well wires (QWWs) have been studied with the use of variational solutions to the effective mass equation. The results show that both the abso- lute value of the electron-phonon interaction energy and the cyclotron resonance frequency de- crease with the increase of the sizes of QWWs, and also that the cyclotron resonance frequency in- creases with the external magnetic field.
文摘A theory of triple magnetopolarons in an isolated quantum well in a strong magnetic field was developed. We study the behavior of the magnetooptical absorption peaks corresponding to the transitions of an electron at the Landau level with quantum numbers n ≥ 2. For n = 2 at the point of equality of cyclotron frequency and the frequency of optical phonon (LO), there is a cross of three terms of the electron-phonon system (the electron at the Landau level n = 2, the electron at n = 1, and the optical phonon and electron at n = 0 and two phonons), considered as a function of the cyclotron frequency. Interaction with phonons takes off the degeneracy of the terms and leads to three disjoint branches of the electron-phonon spectrum. The theory predicts that in the resonant magnetic field, the peak of magnetooptical absorption splits into three peaks, the intensity and position of which are dependent in a complex way on the magnitude of the magnetic field and the constant of the electron-phonon coupling.
基金supported by the Natural Science Foundation of Hebei Province(No.A2008000463)the Science and Technology Research and Development Plan of Qinhuangdao(No.201101A027)
文摘Magnetic field and temperature dependence of the properties of the ground state of the strong-coupling bound magnetopolaron in quantum rods （QRs） with hydrogenic impurity is studied by means of the Huybrechts- Lee-Low-Pines transformation method and the quantum statistical theory. The expressions for the ground-state energy and the mean number ofphonons of the magnetopolaron are derived. Results of the numerical calculations show that the bound state of the magnetopolaron cannot be formed when the value of the aspect ratio of the QR, the dielectric constant ratio, the electron-phonon coupling strength or the temperature parameter is small. The larger the deviation of the value of aspect ratio e′ from 1 is, the more it is unfavorable to the stability of the ground state of the magnetopolaron. When the magnetopolaron is in the bound state, the absolute value of its ground-state energy and its mean number ofphonons increase with an increase of the dielectric constant ratio and confinement strength of QRs, but decrease with an increase in the cyclotron frequency of the external magnetic field and the temperature. The absolute value of the ground-state energy and the mean number of phonons of the magnetopolaron decrease with decreasing e′ when e′ 〈 1, but decrease with increasing e′ when e′ 〉 1. They get the maximum value at e′=1.
文摘The superconductivity in (NbTa)<sub>1-X</sub>(HfZrTi)<sub>X</sub> high-entropy alloy is analyzed using the theory of strong-coupled superconductor. It is concluded that (NbTa)<sub>1-X</sub>(HfZrTi)<sub>X </sub>is a strong coupled superconductor. The variation in the superconducting transition temperature from 7.9 K to 4.6 K as x increases from 0.2 to 0.84 arises because of the decrease in electronic band width due to localization and broadening of the band. It is suggested that the decrease in electronic band width is due to crystalline randomness which gives rise to the mobility edge.
