Tunable alexandrite lasers: Development and performance

Cr+3 Distribution in Al1 and Al2 Sites of Alexandrite (BeAl2O4: Cr3+) Induced by Annealing, Investigated by Optical Spectroscopy

“…This material became technologically important from 1974, when its utilization as an active media for laser action became known, through the utilization in a synthetic form [1]. Alexandrite emission can be tuned in the range 700-800nm [2]. There is a great interest for the alexandrite laser in the present days since it has been vastly used for medical purposes, presenting superior performance compared to other lasers [3][4][5].…”

Influence of annealing on X-ray diffraction of natural alexandrite

“…These results may indicate migration of atoms present in the sample, through different phases, as identified by microprobe analysis ͑WDX͒, such as quartz and mica, besides alexandrite. Alexandrite optical absorption has been extensively presented in the literature from 4 K to 300 K ͑Powell et al, 1985;Liu et al, 1995;Walling et al, 1985;Zhang et al, 1993͒. These spectra show two narrow lines close to 680 nm, called R lines, which are identified as Cr 3ϩ lines, associated with ions at sites located on a reflection plane ͑Al 2 sites͒.…”

InP/InGaP quantum-dot SESAM mode-locked Alexandrite laser

“…Due to the broad tuning range (~85 nm) of Alexandrite [12], a careful dispersion management [38] should lead to the generation of even shorter pulses. In addition, more efficient mode locking should be possible by designing QD-SESAMs specifically for Alexandrite laser crystal that has a gain peak around 755 nm wavelength [10,11]. Also, low quantum defect of visible diode pumping [13,14] should lead to efficient and powerful ultrafast Alexandrite oscillators that will be very attractive for various applications including nonlinear frequency conversion [39][40][41][42], multiphoton microscopy [43,44], and ultrafast spectroscopy [45].…”

“…Currently, Ti:sapphire is the most commonly used broadband vibronic laser crystal that can directly generated a few cycle optical pulses [8,9]. On the other hand, Alexandrite (Cr-doped chrysoberyl BeAl2O4) is another example of vibronic laser crystal [10] that has a wide (~100 nm) wavelength tuning range around 750 nm and high thermal conductivity (similar to Ti:sapphire) [11,12]. Its other advantages are highly polarized output radiation and broad absorption bands that can be used for direct pumping with visible laser diodes [13,14].…”