Elimination of zero-order diffraction in digital holography

A simple method to suppress the zero-order diffraction in the reconstructed image of digital holography is presented. In this method, the Laplacian of a detected hologram is used instead of the hologram itself for numerical reconstruction by computing the discrete Fresnel integral. This method can significantly improve the image quality and give better resolution and higher accuracy of the reconstructed image. The main advantages of this method are its simplicity in experimental requirements and convenience in data processing. (C) 2002 Society of Photo-optical Instrumentation Engineers.

Digital holographic aberration compensation in electron holography

This paper proposes a new digital method to compensate for the aberration of an electron objective lens in electron holography. In this method, the object wavefront in the exit pupil plane is numerically reconstructed from a digitized electron hologram, and is corrected by multiplying it with the conjugated phase-error function. Then, an aberration-free image can be obtained by calculating the Fresnel integral of this corrected wavefront. In comparison with traditional methods, this method is much more convenient and accurate. Some verifying experiments are also presented in this paper. (C) 2003 Society of Photo-optical Instrumentation Engineers.

All optical mode-multiplexing using holography and multimode fiber couplers

A spatial light modulator at the transmitter is used in conjunction with a standard multimode coupler at the receiver to modally multiplex 2 × 12.5 Gb/s nonreturn-to-zero channels using direct detection over 2 km of 940 MHz OM2 fiber without electronic processing. The wavelength dependence of this technique over a 4.5 THz band is also investigated. © 2012 IEEE.

Band alignment of InN/GaAs heterojunction determined by x-ray photoelectron spectroscopy

The valence band offset (VBO) of the InN/GaAs heterojunction is directly determined by x-ray photoelectron spectroscopy to be 0.94 +/- 0.23 eV. The conduction band offset is deduced from the known VBO value to be 1.66 +/- 0.23 eV, and a type-II band alignment forms at the InN/GaAs heterojunction. (C) 2008 American Institute of Physics.

Valence band offset of MgO/4H-SiC heterojunction measured by x-ray photoelectron spectroscopy

The valence band offset (VBO) of MgO (111)/4H-SiC heterojunction has been directly measured by x-ray photoelectron spectroscopy. The VBO is determined to be 3.65 +/- 0.23 eV and the conduction band offset is deduced to be 0.92 +/- 0.23 eV, indicating that the heterojunction has a type- I band alignment. The accurate determination of the valence and conduction band offsets is important for the applications of MgO/SiC optoelectronic devices. (C) 2008 American Institute of Physics.

Valence band offset of ZnO/4H-SiC heterojunction measured by x-ray photoelectron spectroscopy

The valence band offset (VBO) of the wurtzite ZnO/4H-SiC heterojunction is directly determined to be 1.61 +/- 0.23 eV by x-ray photoelectron spectroscopy. The conduction band offset is deduced to be 1.50 +/- 0.23 eV from the known VBO value, which indicates a type-II band alignment for this heterojunction. The experimental VBO value is confirmed and in good agreement with the calculated value based on the transitive property of heterojunctions between ZnO, SiC, and GaN. (C) 2008 American Institute of Physics.

Valence band offset of MgO/InN heterojunction measured by x-ray photoelectron spectroscopy

MgO may be a promising gate dielectric and surface passivation film for InN based devices and the valence band offset of MgO/InN heterojunction has been measured by x-ray photoelectron spectroscopy. The valence band offset is determined to be 1.59 +/- 0.23 eV. Given the experimental band gap of 7.83 for the MgO, a type-I heterojunction with a conduction band offset of 5.54 +/- 0.23 eV is found. The accurate determination of the valence and conduction band offsets is important for use of MgO/InN electronic devices. (c) 2008 American Institute of Physics.