Relativistic corrections in displacement measuring interferometry

Relativistic corrections in displacement measuring interferometry

Displacement measuring interferometry is based on measuring the Doppler frequency shift that a beam of radiation undergoes upon reflection off a mirror connected to a moving stage. Usually the velocity of the reflecting stage is very small compared to the speed of light and is therefore deduced using the classical expression for the Doppler shift. We calculate relativistic corrections to the Do...

A displacement-measuring instrument utilizing self-mixing interferometry

We develop a self-mixing laser interferometer for the measurement of displacements on a generic target surface. The measurement is based on the bright-speckle tracking, a technique we have recently proposed to solve amplitude fading associated with the speckle statistics when the displacement to be covered is well in excess of the speckle longitudinal size. We implement the dynamical tracking o...

Relativistic corrections in magnetic systems

We present a weak-relativistic limit comparison between the Kohn-Sham-Dirac equation and its approximate form containing the exchange coupling, which is used in almost all relativistic codes of density-functional theory. For these two descriptions, an exact expression of the Dirac Green’s function in terms of the nonrelativistic Green’s function is first derived and then used to calculate the e...

Tropospheric Heterogeneities Corrections in Differential Radar Interferometry

Differential radar interferometry (DInSAR) has been used more and more widely to monitor crustal deformations due to underground mining and oil extraction, earthquakes, volcanoes, landslides, and so on. However, tropospheric heterogeneities have been identified as one of the major errors in DInSAR, which can be up to 40cm as derived from dual-frequency GPS measurements in the example given in t...

Effective Hamiltonians with Relativistic Corrections