Scanning tunneling spectroscopy

Scanning tunneling spectroscopy (english scanning tunneling spectroscopy STS) is a further development of the scanning tunneling microscope. It can be used the local ( near-surface ) density of states ( LDOS ) of electrons ( or holes, thus missing electrons ) measure. Using a scanning tunneling microscope in which, in addition to applying the previous DC voltage, an AC voltage to the measuring tip. Then slowly varies the DC voltage which brings the top of the potential, and contributes to, the said passing the voltage to be done at each pixel.