We analyze the particular behavior exhibited by a chaotic waves field containing Peregrine soliton and Akhmediev breathers. This behavior can be assimilated to a tree with “roots of propagation” which propagate rand...We analyze the particular behavior exhibited by a chaotic waves field containing Peregrine soliton and Akhmediev breathers. This behavior can be assimilated to a tree with “roots of propagation” which propagate randomly. Besides, this strange phenomenon can be called “tree structures”. So, we present the collapse of dark and bright solitons in order to build up the above mentioned chaotic waves field. The investigation is done in a particular nonlinear transmission line called chameleon nonlinear transmission line. Thus, we show that this line acts as a bandpass filter at low frequencies and the impact of distance, frequency and dimensionless capacitor are also presented. In addition, the chameleon’s behavior is due to the fact that without modifying the appearance structure, it can present alternatively purely right- or left-handed transmission line. This line is different to the composite one.展开更多
We study theoretically the heat originated from electron-phonon coupling in a spintronic device composed of a semi- conductor quantum dot attached to one spin battery and one ferromagnetic lead. It is found that the p...We study theoretically the heat originated from electron-phonon coupling in a spintronic device composed of a semi- conductor quantum dot attached to one spin battery and one ferromagnetic lead. It is found that the phenomenon of the negative differential of the heat current, which has previously been predicted in the charge-based device, disappears due to the Pauli exclusion principle resulted from the presence of the spin battery. Under some conditions, huge heat in the heat generation induced by resonant phonon emitting processes also disappears in this spin-based device. Furthermore, we find that the ferromagnetism of the lead can be used to effectively adjust the magnitude of the heat current in different dot level ranges. The proposed system is realizable by current technology and may be useful in designing high-efficiency spintronic components.展开更多
Heat generated by electric current in a quantum dot device contacting a phonon bath is studied using the non- equilibrium Green function technique. Spin-polarized current is generated owing to the Zeeman splitting of ...Heat generated by electric current in a quantum dot device contacting a phonon bath is studied using the non- equilibrium Green function technique. Spin-polarized current is generated owing to the Zeeman splitting of the dot level. The current＇s strength and the spin polarization are further manipulated by changing the frequency of an applied photon field and the ferromagnetism on the leads. We find that the associated heat by this spin- polarized current emerges even if the bias voltage is smaller than the phonon energy quanta and obvious negative differential of the heat generation develops when the photon frequency exceeds that of the phonon. It is also found that both the strength and the resonant peaks＇ position of the heat generation can be tuned by changing the value and the arrangement configurations of the magnetic moments of the two leads, and then provides an effective method to generate large spin-polarized current with weak heat. Such a result may be useful in designing low energy consumption spintronic devices.展开更多
A new type of macro-micro-macro triple electrode is fabricated. The kinetic equation is obtained by using the decrease in collection current to determine the kinetic constant of homogeneous catalytic reaction, the met...A new type of macro-micro-macro triple electrode is fabricated. The kinetic equation is obtained by using the decrease in collection current to determine the kinetic constant of homogeneous catalytic reaction, the method can be used to study homogeneous chemical reaction with any magnitude of kinetic constant, and overcomes the disadvantages that the microelectrode is only suitable for fast catalytic reaction.展开更多
文摘We analyze the particular behavior exhibited by a chaotic waves field containing Peregrine soliton and Akhmediev breathers. This behavior can be assimilated to a tree with “roots of propagation” which propagate randomly. Besides, this strange phenomenon can be called “tree structures”. So, we present the collapse of dark and bright solitons in order to build up the above mentioned chaotic waves field. The investigation is done in a particular nonlinear transmission line called chameleon nonlinear transmission line. Thus, we show that this line acts as a bandpass filter at low frequencies and the impact of distance, frequency and dimensionless capacitor are also presented. In addition, the chameleon’s behavior is due to the fact that without modifying the appearance structure, it can present alternatively purely right- or left-handed transmission line. This line is different to the composite one.
基金supported by the National Natural Science Foundation of China(Grant No.61274101)
文摘We study theoretically the heat originated from electron-phonon coupling in a spintronic device composed of a semi- conductor quantum dot attached to one spin battery and one ferromagnetic lead. It is found that the phenomenon of the negative differential of the heat current, which has previously been predicted in the charge-based device, disappears due to the Pauli exclusion principle resulted from the presence of the spin battery. Under some conditions, huge heat in the heat generation induced by resonant phonon emitting processes also disappears in this spin-based device. Furthermore, we find that the ferromagnetism of the lead can be used to effectively adjust the magnitude of the heat current in different dot level ranges. The proposed system is realizable by current technology and may be useful in designing high-efficiency spintronic components.
基金Supported by the National Natural Science Foundation of China under Grant No 61274101
文摘Heat generated by electric current in a quantum dot device contacting a phonon bath is studied using the non- equilibrium Green function technique. Spin-polarized current is generated owing to the Zeeman splitting of the dot level. The current＇s strength and the spin polarization are further manipulated by changing the frequency of an applied photon field and the ferromagnetism on the leads. We find that the associated heat by this spin- polarized current emerges even if the bias voltage is smaller than the phonon energy quanta and obvious negative differential of the heat generation develops when the photon frequency exceeds that of the phonon. It is also found that both the strength and the resonant peaks＇ position of the heat generation can be tuned by changing the value and the arrangement configurations of the magnetic moments of the two leads, and then provides an effective method to generate large spin-polarized current with weak heat. Such a result may be useful in designing low energy consumption spintronic devices.
文摘A new type of macro-micro-macro triple electrode is fabricated. The kinetic equation is obtained by using the decrease in collection current to determine the kinetic constant of homogeneous catalytic reaction, the method can be used to study homogeneous chemical reaction with any magnitude of kinetic constant, and overcomes the disadvantages that the microelectrode is only suitable for fast catalytic reaction.
