Mechanical SET goes ultrasonic

From nanotechweb.org: tech update:

Mechanical single-electron transistors (MSETs) are fundamentally limited by unwanted interactions with the electrical mechanisms used to excite them. Researchers in Germany have now overcome this problem by using ultrasonic waves instead of electrical currents as the excitation source - an important step forward in making high-performance devices. Scientists first proposed the mechanical single-electron transistor (MSET) back in 1998. However, such devices - which are the fastest, most sensitive electrometers available today - need to be excited by an electric current, which increases the risk of electrical cross talk. Now, Daniel Koenig, Eva Weig and Jorg Kotthaus of the Ludwig-Maximillians University in Munich say that this difficulty can be overcome by mechanically exciting the MSET via ultrasonic waves produced by a piezo actuator. Moreover, the MSET is placed in a Faraday cage, which shields the devices against interfering signals from the environment. The ultrasonic waves travel through the Faraday cage onto the sample chip and excite the MSET.

Read the whole article