Diode pumping and laser properties of Yb:Ho:YAG

Spectroscopic investigation and heat generation of Yb^3+/Ho^3+ codoped aluminosilicate glasses looking for the emission at 2 μm

“…Ho-based infrared lasers at ∼2.0 μm were also used in medical operations involving coagulative cutting and tissue welding [15][16][17][18][19] since liquid water has high absorption at this wavelength [20,21]. Motivated by those applications and with the intent of optimizing this 5 I 7 → 5 I 8 emission, several other Ho-based laser systems have been studied in the recent years in many hosts, such as crystalline [3,22], glasses, and optical fibers [23].…”

Populations and Emission Properties of the 5I6 and 5I7 Levels in Ho3+ Doped into PbO–Bi2O3–Ga2O3 Glasses

“…The sensitizers used to increase the emission efficiencies of Ho 3+ ions were Tm 3+ and Yb 3+ 4,6 . In particular, doping of Yb 3+ has been preferred since Yb 3+ ions have only one excited state and therefore do not suffer from any undesirable excited‐state absorption.…”

“…In addition, the commercial InGaAs laser operating at 970 nm can be used to excite the Yb 3+ ions to the 2 F 5/2 level. Energy transfer from the Yb 3+ : 2 F 5/2 level to the 5 I 5 level of Ho 3+ is possible through the phonon‐assisted transfer process 6 …”

Unusual power-dependent and time-dependent upconversion luminescence in nanocrystals Y2O3: Ho3+/Yb3+

“…Since the publication of these reports, infrared to visible UCL in nanocrystals has attracted considerable attention due to its potential application in infrared detection, molecule recognition and three-dimensional displays [6][7][8]. It is well known that Ho 3+ is a suitable active ion for the upconversion laser and the Ho 3+ -Yb 3+ is also a highly efficient UCL system [9][10][11][12]. However, the report on UCL of Ho 3+ -Yb 3+ codoped nanocrystals is quite rare until now.…”