The intrinsic and dynamic kinetic energies the potential of electron states in hydrogen atom were determined using operator formalism Schrödinger’s nonrelativistic equation. Intrinsic momentum operator, while for ℓ ≠ 0, additional spinning fields angular operator. All 10 up to principal quantum number n = 3 all 4 m 7, l analyzed. two forms energy can only be explained with an field representation. total conformed well-known 1/n2 rule. Angular analysis 2P1/2 state provided a rate; addition,...

The authors review those characterization techniques that have played significant roles in the development of HgCdTe infrared detector technology. They focus on two specific devices achieved widespread application for detection LWIR (8-12 mu m) and VLWIR (12-20 spectral regions: simple n-type photoconductor P-on-n LPE heterojunction photodiode. device physics these detectors, relate performance to starting material properties processing parameters, describe most important had a role their...

The optical absorption below the edge in x=0.2 and x=0.3 Hg1−xCdxTe alloys has been investigated. In p-type of both compositions at wavelengths equivalent to approximately 0.75 Eg 20 μm, measured cross sections 90 K were close intervalence calculated using first-order Kane k⋅p theory with a bandstructure parameter P 8.4×10−8 eV cm heavy hole mass 0.5 m. For Hg0.8Cd0.2Te 1.8×10−15 cm2 for between 15 μm. Hg0.7Cd0.3Te , increased from 1×10−15 5 μm about 3×10−15 At higher temperatures decreased;...

The liquidus temperatures for have been determined for, , and compositions by differential thermal analyses. films with of grown liquid phase epitaxy on (111) A oriented substrates. Cd segregation coefficient has to be . Films at around 550°C from 3 mm thick melts slow cooling rates showed thicknesses close those expected equilibrium growth. residual impurity in the LPE was usually n‐type less than 1015 cm−3 better films. Photovoltaic diodes fabricated shown performance comparable bulk crystals.

A new contactless optical modulation technique for the determination of photogenerated carrier lifetimes in semiconductors is presented. The consists measuring transmitted intensity a dc probe beam (h/ω<Eg) due to modulated pump (h/ω≳Eg). fractional change transmission proportional excess lifetime. Data are presented 0.1–4 μ sec measured by this p-type and near-intrinsic Hg0.7Cd0.3Te samples at 300 K.

We have applied the technique of optical modulation spectroscopy to narrow-gap semiconductor Hg1−xCdxTe. This consists measuring change ΔIp in transmitted intensity Ip a tunable dc probe beam (with photon energy h/ωP<Eg ) due fixed-wavelength chopped pump h/ωP≳Eg ). The ΔIp/Ip vs h/ωp spectra were measured for liquid phase epitaxial Hg1−xCdxTe samples at 94 K with x≅0.24–0.37. All show three distinct peaks. strongest peak occurs near Eg. other two peaks are relatively sharp and occur...

Optical absorption measurements at the fundamental edge in high purity and stochiometrically doped p-type Hg0.7Cd0.3Te show to be significantly influenced by valence band tailing due native Hg vacancy acceptor defects. The coefficient αe for transitions across gap increases as αe=α0 exp k(E−E0); ambient temperatures k=148 eV−1, this value decreases k=105 eV−1 concentrations of around 2×1016 cm−3.

Photoinduced absorption modulation near the band gap is used for first time to measure excess electron lifetime and energy in several samples of bulk LPE Hg0.2Cd0.8Te. The were primarily n-type with carrier concentrations from 3×1013 2×1015 cm−3. fractional transmission change ΔI(E)/I(E) Eg, due a nonequilibrium Burstein–Moss shift, described by simple theory based on bandfilling, empirical modifications include broadening effects films. Lifetimes are determined three methods: (1) ΔI/I...

An investigation of the 4f3 4I9/2, 4I15/2, 4F3/2, and 4F9/2 multiplet splittings Nd3+ in YAG was undertaken on basis an explicit point-charge model. A fit between optical data 20 calculated energy levels made within a 22.7 cm−1 standard deviation using only three adjustable parameters. physical representation crystal field at sites could not be achieved solely model surrounding ion point charges located sites. However, when effects strong covalency contribution to were simulated by effective...

This Letter reports on the vapor-phase epitaxy of GaN basal plane oriented sapphire using a nitrogen arcjet plasma expanding into low pressure. A hydrogen-free and carbon-free growth environment was achieved by use pure Ga vapor source introduced downstream plume electron-assisted evaporation. Heteroepitaxial rates 8 μm/h were obtained in studies reported. We believe these are highest reported for non-chemical decomposition process. The attributed to very high atom fluxes arc dissociation...

The design of a flashlamp triggering and driving circuit is described for the short pulse pumping Nd3+ YAlO crystal suitable Q-switched operation. special features this system were prepulse pulsing immediately before main pulse, new method based upon saturable choke. An increase in laser efficiency reproducibility was obtained when mode operation used.