Polarity-sensitive THz-sampling using the Quantum Dot Stark-Effect

Mr. Moritz B. Heindl1, Mr. Hua Zhu2, Prof. Moungi Bawendi2, Prof. Georg Herink1
1Experimentalphysik 8, Universit├Ąt Bayreuth, Bayreuth, Germany. 2Department of Chemistry, Cambridge, USA


We present an electro-absorptive THz antenna for the polarity-sensitive coherent sampling of THz lightwaves based on quantum dots. Introducing AC-bias, we effectively break the symmetry of the quantum-confined Stark effect in a layer of colloidal CdS-CdSe quantum dots. The alternating bias allows for the polarity-sensitive readout of THz-fields using differentially detected ultrafast electro-absorption. We investigate the underlying scaling behaviors, demonstrate first applications and discuss the prospects of THz-super-resolution imaging with Quantum-probe field microscopy (QFIM).