Efficient laser operation of diode-pumped Nd:KGd(WO_4)_2 crystal at 1067 μm

Chen, Youming; Major, L.; Kushawaha, V.

doi:10.1364/ao.35.003203

Cited by 23 publications

(7 citation statements)

References 5 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…We prefer the ®rst assertion. Some other authors have reported unit-cell parameters with inappropriate space groups; the published results are inconsistent (Chen et al, 1996;Kuleshov et al, 1997).…”

Section: Structural Studymentioning

confidence: 99%

Structural study of monoclinic KGd(WO₄)₂and effects of lanthanide substitution

et al. 2001

View full text Add to dashboard Cite

The crystal structure of monoclinic KGd(WO4)2 (KGW) has been refined at room temperature by using single‐crystal X‐ray diffraction data. The unit‐cell parameters are a = 10.652 (4), b = 10.374 (6), c = 7.582 (2) Å, β = 130.80 (2)°, with Z = 4, in space group C2/c. The linear thermal expansion tensor has been determined and the principal axes are [302], [010] and [106]. The principal axis with maximum thermal expansion ( = 23.44 × 10−6 K−1), , was located 12° from the c axis. Undoped crystals of KGW and crystals that were partially doped by Pr, Nd, Ho, Er, Tm and Yb were grown by the top‐seeding‐solution growth slow‐cooling method. The effect of doping on the KGW structure was observed in the cell parameters and in morphological changes. The changes in parameters follow the changes in lanthanide ionic radii. The doped crystals show {021} and {21} faces in addition to the {110}, {11}, {010}, {130} and {310} faces which basically follow the habit of the undoped KGW crystals. The development of the faces is related to the number of the most important periodic bond chains parallel to them.

show abstract

Section: Structural Studymentioning

confidence: 99%

Structural study of monoclinic KGd(WO₄)₂and effects of lanthanide substitution

et al. 2001

View full text Add to dashboard Cite

show abstract

“…KRE(WO 4 ) 2 (hereafter KRW) matrices have large values of the χ 3 non-linear constant describing the Raman coupling. Further, the 4 F 3/2 → 4 I 11/2 emission of Nd 3+ in KGd(WO 4 ) 2 (hereafter KGW) is as efficient as in the widely used YAG host, but it has a lower laser threshold in KGW [2]. Laser emission in the 1.06-1.07 µm region has also been observed at room temperature using the 1 D 2 → 3 F 4 Pr 3+ emission in KRW crystals [3].…”

Section: Introductionmentioning

confidence: 99%

Optical spectroscopy of Pr³⁺in KGd(WO₄)₂single crystals

Zaldo

Rico

Cascales

et al. 2000

J. Phys.: Condens. Matter

View full text Add to dashboard Cite

The polarized optical absorption (OA) and photoluminescence of Pr3+ doped KGd(WO4)2 (KGW) single crystals have been measured at selected temperatures between 7 and 300 K. For the studied Pr concentrations, [Pr] = 0.03×1020-1.9×1020 cm-3, a unique site is observed. 74 energy levels were experimentally determined for this site and labelled with the appropriate A or B irreducible representations corresponding to the C2 symmetry of the Gd point site in KGW. The set was fitted to a Hamiltonian of adjustable parameters including free-ion as well as real Bqk and complex Sqk crystal-field parameters. A good simulation of the experimental crystal field energies was achieved with a root mean square deviation σ = 15.3 cm-1. Distortions in the oxygen bonds to Pr3+ are found to contribute to the broadening of some OA bands, particularly those related to the 1D2 multiplet. The OA edge is determined by the interconfigurational 4f→4f15d1 Pr3+ transition peaking at 34 200 cm-1. From the average 300 K OA cross sections the radiative lifetimes of the Pr3+ multiplets have been calculated considering the standard and modified Judd-Ofelt (JO) theories. A better agreement with the experimental results is obtained by the standard theory: the average JO parameters obtained at ω̄2 = 12.0×10-20 cm2, ω̄4 = 8.15×10-20 cm2 and ω̄6 = 2.64×10-20 cm2. Electrons excited to the 3P0 multiplet decay very efficiently to the 1D2 multiplet even at 15 K. In samples with [Pr]⩾0.3×1020 cm-3 the excitation of the 1D2 multiplet decays non-radiatively by an electric dipole-dipole transfer between Pr neighbours.

show abstract

“…KGW crystals have been also used as a laser host for Nd 3+ ions because of the high efficiency of the 4 F 3/2 → 4 I 11/2 transition [11,12] as well as a host for other rare-earth laser ions [8]. Recently, some research has focused attention on crystals with relevant cubic nonlinearity χ (3) because with these materials it is possible to obtain unconventional lasers, such as lasers with stimulated-Raman-scattering (SRS) frequency self-conversion.…”

mentioning

confidence: 99%

Crystalline structure and optical spectroscopy of Er3+-doped KGd(WO4)2 single crystals

et al. 1999

View full text Add to dashboard Cite

Abstract. KGd(WO 4 ) 2 single crystals doped with Er 3+ have been grown by the flux top-seeded-solution growth method. The crystallographic structure of the lattice has been refined, being the lattice constants a = 10.652(4), b = 10.374(6), c = 7.582(2) Å, β = 130.80(2)• . The refractive index dispersion of the host has been measured in the 350-1500 nm range. The optical absorption and photoluminescence properties of Er The technological interest in the development of solidstate lasers for application in long-distance optical communications has promoted the study of laser ions with an emission close to the minimum of the optical losses in silica fibers, namely 1.5 µm. The present development of a new laser generation requires us to find crystals with low excitation threshold and suited to be excited by the emission of diode lasers. Er 3+ only has weak absorption bands in the 600-1000 nm region, but its photoluminescence can be sensitised by energy transfer from Yb 3+ , which shows a strong optical absorption in the 900-1000 nm range. This region overlaps the emission of InGaAs diode lasers. As a matter of fact, InGaAs diodepumped room-temperature laser operation has been recently demonstrated in KGd(WO 4 ) 2 :Yb:Er crystals [7] (hereafter KGd(WO 4 ) 2 is abbreviated as KGW), however the efficiency of the process was weak and the physical processes involved were poorly understood. Moreover, Er has been used to sensitise the Tm 3+ emission in KGW crystals at liquid nitrogen temperature [8].Despite the relevance of the optical properties of Er 3+ in KGW crystals, its spectroscopic properties have been reported at 77 K only for the 4 S 3/2 or lower energy levels [9,10]. The present work reports a spectroscopic study of the Er 3+ ions incorporated in KGW crystals grown by the flux top-seeded-solution growth (TSSG) technique.KGW crystals have been also used as a laser host for Nd 3+ ions because of the high efficiency of the 4 F 3/2 → 4 I 11/2 transition [11,12] as well as a host for other rare-earth laser ions [8]. Recently, some research has focused attention on crystals with relevant cubic nonlinearity χ (3) because with these materials it is possible to obtain unconventional lasers, such as lasers with stimulated-Raman-scattering (SRS) frequency self-conversion. The KGW:Nd possesses an effective cubic nonlinearity of about 10 −13 esu and presents a good efficiency in the process of SRS self-conversion [13].In view of the relevance of the KGW lattice host, we have also performed a refinement of the crystal structure, in order to improve the currently known lattice constants and to help in the discussion of the local lattice site symmetry when required. Further, we discuss the orientation of the indicatrix of the crystal with regards to the crystallographic axes and we have obtained the value of the refractive indices in a wide spectral region.

show abstract

Efficient laser operation of diode-pumped Nd:KGd(WO_4)_2 crystal at 1067 μm

Cited by 23 publications

References 5 publications

Structural study of monoclinic KGd(WO₄)₂and effects of lanthanide substitution

Structural study of monoclinic KGd(WO₄)₂and effects of lanthanide substitution

Optical spectroscopy of Pr³⁺in KGd(WO₄)₂single crystals

Crystalline structure and optical spectroscopy of Er3+-doped KGd(WO4)2 single crystals

Contact Info

Product

Resources

About

Efficient laser operation of diode-pumped Nd:KGd(WO_4)_2 crystal at 1067 μm

Cited by 23 publications

References 5 publications

Structural study of monoclinic KGd(WO4)2and effects of lanthanide substitution

Structural study of monoclinic KGd(WO4)2and effects of lanthanide substitution

Optical spectroscopy of Pr3+in KGd(WO4)2single crystals

Crystalline structure and optical spectroscopy of Er3+-doped KGd(WO4)2 single crystals

Contact Info

Product

Resources

About

Structural study of monoclinic KGd(WO₄)₂and effects of lanthanide substitution

Structural study of monoclinic KGd(WO₄)₂and effects of lanthanide substitution

Optical spectroscopy of Pr³⁺in KGd(WO₄)₂single crystals