Lets take a single layer of MoS2. Lets attach it to a surface in such a way that it can be stretched (or compressed) and there you have it: A strain tunable single-layer MoS2 photodetector. A device which uses strain to change the electrical and optical properties of 2D materials. In particular they’ve proven that with this method, they can reversibly change the photoresponsivity, the response time and the spectral bandwidth of single layered MoS2.
At Dr. Castellanos Lab, they are excelling at beautiful and elegant research. “… we demonstrated that applying tensile biaxial strain to the MoS2 device can be an effective strategy to increase both the responsivity and the wavelength bandwidth of the photodetector (at the expense of a slower response time), while compressive strain can be exploited to yield faster photodetectors (although with a lower photoresponse and with a narrower wavelength bandwidth). This adaptable optoelectronic performance of this device can be very useful to adjust the photodetector operation to different lighting conditions, similarly to human eye adaptability (scotopic vision during the night vs. photopic vision during the daylight).”
Their research is a collaboration between ICMM-CSIC, Imdea Nanociencia and the State Key Laboratory of Tribology, Tsinghua University, Beijing and has been recognized with the inner cover of Materials Today.