Single electron transistors as far-infrared photon detectors

The single electron transistor (SET) is able to detect polarization within small objects caused by individual electrons. This property can be utilized to realize high sensitive detection of electromagnetic waves reaching single photon counting level, if individual photons affect on an electron distribution within tiny devices capacitively coupled to SET. The best candidates for the detection are quantum dots (QDs) in two-dimensional electron gas (2DEG). Here, we explore far infrared (FIR) detectors based on two photo-excitation mechanisms in 2DEG: (i) cyclotron resonance (CR) absorption in high magnetic fields and (ii) collective mode excitations at a characteristic frequency of the parabolic confinement potential in the absence of magnetic fields.