Highly reflective mirrors

Uses. Electroplating manufacture of rhodium-platinum alloys manufacture of high-reflectivity mirrors... 

The photon thus induced to be emitted has the same phase relationship as the inducing photon. Further amplification of this coherent emission is brought about in a resonant optical cavity containing two highly reflecting mirrors, one of which allows the amplified beam to come out, either through a pin-hole or by a little transmission (Section 10.4). 

In conclusion, the optical gain of quantum well GaN/AlGaN was estimated, based on the density-matrix theory. The introduction of GaN quantum wells as active regions in GaN-based surface emitting lasers can reduce the threshold current to lower than that of bulk GaN layers. Sub-milliampere operation can be expected by reducing the device diameter. Fabrication processes such as highly reflective mirrors and dry-etch techniques have been demonstrated. 

Figure 10. Schematics of the experimental setup for intracavity laser absorption spectroscopy (ICLAS). CD chopper driver PM power meter Mj, M2, M3, M4 spherical high reflection mirrors Mp = pump mirror MN monochromator PMT photomultiplier SP silicon photocell PC Pockels cell WF wedged filter LIA lock-in amplifier R recorder MS microscope OF optical fiber S sample (solution on BLM) IEM instruments for electrical measurements (see Figure 2).

EBIT as shown in Fig. 2. The trapped Si + ions will lie at the laser beam waist within the enhancement cavity, and to keep the finesse of the cavity as high as possible it is necessary for the high reflectivity mirrors to lie within the EBIT vacnnm chamber. The Ti sapphire laser will be locked to the high finesse cavity nsing the rf sideband locking techniqne [33]. Fast frequency fluctuations will be corrected using an acousto-optic modulator in a double-pass configuration, whilst the slower branch of the servo loop will use a piezo-mounted mirror in the laser cavity. 

Rhodium is used as an alloy with platinum, and as a catalyst. It is also used as a corrosion-resistant electroplate for protecting silverware from tarnishing, for making high-reflectivity mirrors for cinema projectors, and searchlights. It can be used as a catalyst for chemical reactions, and in jewelry. In fact, rhodium is a very common plating for inexpensive jewelry because it is extremely shiny and tarnish resistant. It is actually a very expensive metal however, only need a microscopically thin layer is needed. 

Electrochemical metal removal processes have been developed and utilized by industry for a variety of different applications. Electropolishing as an industrial finishing operation was first demonstrated by Jaquet in 1930 [113]. Metals such as aluminum, steel, brass, cooper, and silver/iuckel alloys are anodized to produce a highly reflective mirror fliush. The surface to be polished is the anode with a current density in the range of 0.100 to 0.800 A/cm. The electrolyte is typically phosphoric... 

Electropolishing is a process closely related to anodizing which is used to produce metal articles with a highly reflecting mirror finish. Again the most common metal to be electropolished is aluminium, but the procedure is also used for steel, brass, copper and nickel/silver alloy. 

With very high reflectivity mirrors long absorption paths can be realized which increases the absorption a L by a factor up to 10". ... 

One needs really high reflectivity mirrors in order to reach a sensitivity comparable to other sensitive absorption techniques. 

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