In this paper a resonant tunnelling quantum well infrared photodetector (RT-QWIP) is discussed. Each period of this photodetector structure comprises of a resonant tunnelling structure (AlAs/AlGaAs/AlAs) nearby a quantum well (AlGaAs/GaAs). In this photodetector, photocurrent is produced when an electron makes a transition from the ground state of the well to an excited state which is coupled t...

Interband tunnelling of carriers through a forbidden energy gap, known as Zener tunnelling, is a phenomenon of fundamental and technological interest. Its experimental observation in the Esaki p-n semiconductor diode has led to the first demonstration and exploitation of quantum tunnelling in a condensed matter system. Here we demonstrate a new type of Zener tunnelling that involves the resonan...

Introduction: Negative resistance elements are important components in oscillator circuits and form the basis of many other nonlinear circuits. Resonant tunnelling diodes (RTDs) have attracted much attention due to their wide-bandwidth negative differential resistance (NDR), up to hundreds of GHz [1]. Because RTDs can be easily integrated in electronic and optoelectronic circuits, the applicati...

–We investigate spin-dependent interband tunnelling in a ferromagnetic (Ga,Mn)As/ GaAs Zener diode. The ferromagnetic pn-junction is fabricated with a Mn-doped p-type GaAs layer on top of a nonmagnetic n-type GaAs substrate. When both sides of the junction are heavily doped, a large magnetic-field–dependent tunnelling effect can be seen at low temperatures in the measured current-voltage (I-V )...

–We investigate spin-dependent interband tunnelling in a ferromagnetic (Ga,Mn)As/ GaAs Zener diode. The ferromagnetic pn-junction is fabricated with a Mn-doped p-type GaAs layer on top of a nonmagnetic n-type GaAs substrate. When both sides of the junction are heavily doped, a large magnetic-field–dependent tunnelling effect can be seen at low temperatures in the measured current-voltage (I-V )...