Control of the electron spectrum of a quasi-one-dimensional conductor K$_{0.3}$MoO$_3$ with the use of a microcontact

When an electric field is applied to a Peierls quasi-one-dimensional conductor K$_{0.3}$MoO$_3$, a change in conductivity is observed in the vicinity of the point contact. This change is due to a strong local distortion of the charge density wave in the pinned state. In this case, the chemical potential can be varied over a wide range by changing the conductivity from the $n$ type to the $p$ type. The local position of the chemical potential can be determined by the method proposed; in particular, the low-temperature anomaly of conductivity is explained.