EP2084792A2 - Laser à semi-conducteurs pompé de manière optique au moyen d'un milieu actif co-dopé - Google Patents

Laser à semi-conducteurs pompé de manière optique au moyen d'un milieu actif co-dopé

Info

Publication number
EP2084792A2
EP2084792A2 EP07826745A EP07826745A EP2084792A2 EP 2084792 A2 EP2084792 A2 EP 2084792A2 EP 07826745 A EP07826745 A EP 07826745A EP 07826745 A EP07826745 A EP 07826745A EP 2084792 A2 EP2084792 A2 EP 2084792A2
Authority
EP
European Patent Office
Prior art keywords
ions
laser
solid
state
state laser
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Withdrawn
Application number
EP07826745A
Other languages
German (de)
English (en)
Inventor
Ulrich Weichmann
Peter J. Schmidt
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Philips Intellectual Property and Standards GmbH
Koninklijke Philips NV
Original Assignee
Philips Intellectual Property and Standards GmbH
Koninklijke Philips Electronics NV
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Philips Intellectual Property and Standards GmbH, Koninklijke Philips Electronics NV filed Critical Philips Intellectual Property and Standards GmbH
Priority to EP07826745A priority Critical patent/EP2084792A2/fr
Publication of EP2084792A2 publication Critical patent/EP2084792A2/fr
Withdrawn legal-status Critical Current

Links

Classifications

    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01S—DEVICES USING THE PROCESS OF LIGHT AMPLIFICATION BY STIMULATED EMISSION OF RADIATION [LASER] TO AMPLIFY OR GENERATE LIGHT; DEVICES USING STIMULATED EMISSION OF ELECTROMAGNETIC RADIATION IN WAVE RANGES OTHER THAN OPTICAL
    • H01S3/00—Lasers, i.e. devices using stimulated emission of electromagnetic radiation in the infrared, visible or ultraviolet wave range
    • H01S3/14—Lasers, i.e. devices using stimulated emission of electromagnetic radiation in the infrared, visible or ultraviolet wave range characterised by the material used as the active medium
    • H01S3/16—Solid materials
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01S—DEVICES USING THE PROCESS OF LIGHT AMPLIFICATION BY STIMULATED EMISSION OF RADIATION [LASER] TO AMPLIFY OR GENERATE LIGHT; DEVICES USING STIMULATED EMISSION OF ELECTROMAGNETIC RADIATION IN WAVE RANGES OTHER THAN OPTICAL
    • H01S3/00—Lasers, i.e. devices using stimulated emission of electromagnetic radiation in the infrared, visible or ultraviolet wave range
    • H01S3/09—Processes or apparatus for excitation, e.g. pumping
    • H01S3/091—Processes or apparatus for excitation, e.g. pumping using optical pumping
    • H01S3/094—Processes or apparatus for excitation, e.g. pumping using optical pumping by coherent light
    • H01S3/0941—Processes or apparatus for excitation, e.g. pumping using optical pumping by coherent light of a laser diode
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01S—DEVICES USING THE PROCESS OF LIGHT AMPLIFICATION BY STIMULATED EMISSION OF RADIATION [LASER] TO AMPLIFY OR GENERATE LIGHT; DEVICES USING STIMULATED EMISSION OF ELECTROMAGNETIC RADIATION IN WAVE RANGES OTHER THAN OPTICAL
    • H01S3/00—Lasers, i.e. devices using stimulated emission of electromagnetic radiation in the infrared, visible or ultraviolet wave range
    • H01S3/14—Lasers, i.e. devices using stimulated emission of electromagnetic radiation in the infrared, visible or ultraviolet wave range characterised by the material used as the active medium
    • H01S3/16—Solid materials
    • H01S3/1601—Solid materials characterised by an active (lasing) ion
    • H01S3/1603—Solid materials characterised by an active (lasing) ion rare earth
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01S—DEVICES USING THE PROCESS OF LIGHT AMPLIFICATION BY STIMULATED EMISSION OF RADIATION [LASER] TO AMPLIFY OR GENERATE LIGHT; DEVICES USING STIMULATED EMISSION OF ELECTROMAGNETIC RADIATION IN WAVE RANGES OTHER THAN OPTICAL
    • H01S3/00—Lasers, i.e. devices using stimulated emission of electromagnetic radiation in the infrared, visible or ultraviolet wave range
    • H01S3/14—Lasers, i.e. devices using stimulated emission of electromagnetic radiation in the infrared, visible or ultraviolet wave range characterised by the material used as the active medium
    • H01S3/16—Solid materials
    • H01S3/1601—Solid materials characterised by an active (lasing) ion
    • H01S3/1603—Solid materials characterised by an active (lasing) ion rare earth
    • H01S3/1605—Solid materials characterised by an active (lasing) ion rare earth terbium
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01S—DEVICES USING THE PROCESS OF LIGHT AMPLIFICATION BY STIMULATED EMISSION OF RADIATION [LASER] TO AMPLIFY OR GENERATE LIGHT; DEVICES USING STIMULATED EMISSION OF ELECTROMAGNETIC RADIATION IN WAVE RANGES OTHER THAN OPTICAL
    • H01S3/00—Lasers, i.e. devices using stimulated emission of electromagnetic radiation in the infrared, visible or ultraviolet wave range
    • H01S3/14—Lasers, i.e. devices using stimulated emission of electromagnetic radiation in the infrared, visible or ultraviolet wave range characterised by the material used as the active medium
    • H01S3/16—Solid materials
    • H01S3/163—Solid materials characterised by a crystal matrix
    • H01S3/1631—Solid materials characterised by a crystal matrix aluminate
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01S—DEVICES USING THE PROCESS OF LIGHT AMPLIFICATION BY STIMULATED EMISSION OF RADIATION [LASER] TO AMPLIFY OR GENERATE LIGHT; DEVICES USING STIMULATED EMISSION OF ELECTROMAGNETIC RADIATION IN WAVE RANGES OTHER THAN OPTICAL
    • H01S3/00—Lasers, i.e. devices using stimulated emission of electromagnetic radiation in the infrared, visible or ultraviolet wave range
    • H01S3/14—Lasers, i.e. devices using stimulated emission of electromagnetic radiation in the infrared, visible or ultraviolet wave range characterised by the material used as the active medium
    • H01S3/16—Solid materials
    • H01S3/163—Solid materials characterised by a crystal matrix
    • H01S3/1631—Solid materials characterised by a crystal matrix aluminate
    • H01S3/1638—YAlO3 (YALO or YAP, Yttrium Aluminium Perovskite)
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01S—DEVICES USING THE PROCESS OF LIGHT AMPLIFICATION BY STIMULATED EMISSION OF RADIATION [LASER] TO AMPLIFY OR GENERATE LIGHT; DEVICES USING STIMULATED EMISSION OF ELECTROMAGNETIC RADIATION IN WAVE RANGES OTHER THAN OPTICAL
    • H01S3/00—Lasers, i.e. devices using stimulated emission of electromagnetic radiation in the infrared, visible or ultraviolet wave range
    • H01S3/14—Lasers, i.e. devices using stimulated emission of electromagnetic radiation in the infrared, visible or ultraviolet wave range characterised by the material used as the active medium
    • H01S3/16—Solid materials
    • H01S3/163—Solid materials characterised by a crystal matrix
    • H01S3/1655—Solid materials characterised by a crystal matrix silicate
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01S—DEVICES USING THE PROCESS OF LIGHT AMPLIFICATION BY STIMULATED EMISSION OF RADIATION [LASER] TO AMPLIFY OR GENERATE LIGHT; DEVICES USING STIMULATED EMISSION OF ELECTROMAGNETIC RADIATION IN WAVE RANGES OTHER THAN OPTICAL
    • H01S3/00—Lasers, i.e. devices using stimulated emission of electromagnetic radiation in the infrared, visible or ultraviolet wave range
    • H01S3/14—Lasers, i.e. devices using stimulated emission of electromagnetic radiation in the infrared, visible or ultraviolet wave range characterised by the material used as the active medium
    • H01S3/16—Solid materials
    • H01S3/163—Solid materials characterised by a crystal matrix
    • H01S3/1668—Solid materials characterised by a crystal matrix scandate
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01S—DEVICES USING THE PROCESS OF LIGHT AMPLIFICATION BY STIMULATED EMISSION OF RADIATION [LASER] TO AMPLIFY OR GENERATE LIGHT; DEVICES USING STIMULATED EMISSION OF ELECTROMAGNETIC RADIATION IN WAVE RANGES OTHER THAN OPTICAL
    • H01S3/00—Lasers, i.e. devices using stimulated emission of electromagnetic radiation in the infrared, visible or ultraviolet wave range
    • H01S3/14—Lasers, i.e. devices using stimulated emission of electromagnetic radiation in the infrared, visible or ultraviolet wave range characterised by the material used as the active medium
    • H01S3/16—Solid materials
    • H01S3/1691—Solid materials characterised by additives / sensitisers / promoters as further dopants
    • H01S3/1698—Solid materials characterised by additives / sensitisers / promoters as further dopants rare earth
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01S—DEVICES USING THE PROCESS OF LIGHT AMPLIFICATION BY STIMULATED EMISSION OF RADIATION [LASER] TO AMPLIFY OR GENERATE LIGHT; DEVICES USING STIMULATED EMISSION OF ELECTROMAGNETIC RADIATION IN WAVE RANGES OTHER THAN OPTICAL
    • H01S5/00—Semiconductor lasers
    • H01S5/30—Structure or shape of the active region; Materials used for the active region
    • H01S5/32—Structure or shape of the active region; Materials used for the active region comprising PN junctions, e.g. hetero- or double- heterostructures
    • H01S5/323—Structure or shape of the active region; Materials used for the active region comprising PN junctions, e.g. hetero- or double- heterostructures in AIIIBV compounds, e.g. AlGaAs-laser, InP-based laser
    • H01S5/32308—Structure or shape of the active region; Materials used for the active region comprising PN junctions, e.g. hetero- or double- heterostructures in AIIIBV compounds, e.g. AlGaAs-laser, InP-based laser emitting light at a wavelength less than 900 nm
    • H01S5/32341—Structure or shape of the active region; Materials used for the active region comprising PN junctions, e.g. hetero- or double- heterostructures in AIIIBV compounds, e.g. AlGaAs-laser, InP-based laser emitting light at a wavelength less than 900 nm blue laser based on GaN or GaP

Definitions

  • the present invention relates to a solid-state laser comprising a gain medium of a solid-state host material, which is doped with rare-earth ions.
  • US 6,816,532 B2 discloses a laser diode exited laser apparatus in which the gain medium is doped with rare-earth ions, in particular with Ho 3+ -, Sm 3+ -, Eu 3+ -, Dy 3+ -, Er 3+ - and Tb 3+ - ions.
  • the solid gain medium is pumped by a GaN based laser diode. Both the excitation and the laser emission of the disclosed laser involve transitions between 4f states of the rare-earth ion. Since the absorption at these transitions is relatively weak, the efficiency of the devices is limited and long interaction lengths like for example in fiber lasers are required.
  • the proposed solid-state laser comprises a gain medium of a solid-state host material, which is co-doped with the Ce 3+ - ions and with ions of a further rare-earth material.
  • the host material is selected such that a lower edge of the 5d band of the Ce 3+ - ion is energetically higher than an upper lasing state of the ions of the further rare-earth material.
  • the proposed all solid-state laser can be pumped efficiently with GaN laser diodes in the wavelength range of for example between 400 and 450 nm.
  • the gain medium absorbs the radiation of the pump laser via the 4f-5d transitions in the Ce 3+ - ion. From the 5d band of the Ce 3+ - ion the energy is transferred to the upper lasing state of the further rare-earth ion which then emits the desired laser radiation through a transition between the upper lasing state and a lower lasing state.
  • the emitted laser wavelength is influenced by the selection of the further rare-earth ions and may further be influenced by the spectral characteristics of the resonator mirrors of the solid-state laser.
  • Ce 3+ - ions with further trivalent rare- earth ions are combinations of Ce 3+ -ions with Pr 3+ , Sm 3+ , Eu 3+ , Dy 3+ and Tm 3+ to design lasers emitting with different wavelengths in the visible wavelength range.
  • the proposed solid-state laser comprises a gain medium of a solid-state host material, which is co-doped with Ce 3+ - ions and Tb 3+ - ions.
  • the laser pumping scheme involves 4f-5d-transitions in Ce 3+ , energy transfer from the Ce 3+ 5d band to the 5 D 4 -state of Tb 3+ , from which laser emission takes place.
  • This scheme is very attractive since it combines the high absorption of 4f-5d-transitions with the known laser properties of rare-earth 4f-4f lasers. Highly integrated, efficient laser devices are therefore possible.
  • the Tb 3+ - ion is very attractive to provide an optically pumped solid-state laser in the green wavelength range, since it has a well isolated 5 D 4 state with a long lifetime in many hosts. From this 5 D 4 -level green emission around 543 nm is very pronounced.
  • the dopant concentration Cce for the Ce 3+ -ions is preferably in the range of 0.01% wt to 5% wt.
  • the appropriate selection of this host material is important in order to achieve the desired laser action.
  • Very advantageous laser operation has been observed when using host materials with an energy gap of at least 6 eV.
  • the host materials also have to ensure the energy transfer between the 5d-band of the Ce 3+ -ions and, for example, the 5 D 4 state of the Tb 3+ ions.
  • the Ce 3+ -ions act as a sensitizer and provide a good absorption of the pump radiation via the 4f-5d transitions, whereas the further rare-earth ions act as the laser active ions.
  • solid-state host materials doped with Ce 3+ -ions are not suited for laser action due to very strong excited state absorption, it was surprisingly found by the inventors of the present invention, that by co-doping the Ce 3+ -ions with further trivalent rare-earth ions and by selecting an appropriate host material, laser action can be achieved in an efficient manner.
  • an all-solid-state laser is realized which can be efficiently pumped by GaN based laser diodes to emit in the green wavelength range.
  • Such all-solid-state laser systems including the pump laser can be manufactured in a highly integrated manner and are in particular suited as light sources for projection systems in display or illumination applications.
  • the optical design of the all-solid-state laser can be chosen as known in the art.
  • a laser can be set up for example in the form of an end pumped rod, similar to other diode pumped solid-state lasers known in the art.
  • the proposed laser can also be designed in the form of a planar waveguide laser, in which the co-doped material is brought to the form of a planar waveguide that is adapted in its geometry to the emission profile of the laser diode.
  • the laser diode and the co-doped conversion medium are preferably placed on a shared cooling structure, which allows for a highly integrated device.
  • the high absorption of the Ce 3+ -ions allows also for transversal pump geometries, in which the laser radiation emerges in a direction perpendicular to the direction of the pump radiation.
  • Fig. 1 an excitation scheme of a preferred embodiment of the proposed laser
  • Fig. 2 an example for an end pumped geometry of the proposed laser
  • Fig. 3 an example of a transversally pumped geometry of the proposed laser.
  • the gain medium of the proposed laser is co-doped with Ce 3+ - and Tb 3+ -ions.
  • the Ce-Tb-laser is pumped with a GaN based laser diode.
  • Figure 1 shows the pumping and lasing scheme of such a solid-state laser.
  • the blue pump radiation 1 of the GaN based laser diode is absorbed via the 4f-5d transition of the Ce 3+ -ions.
  • energy transfer 2 takes place between the 5d band of the Ce 3+ -ions and the upper lasing state ( 5 D 4 state) of the Tb 3+ - ions as is indicated in the figure. From this 5 D 4 state of the Tb 3+ -ions laser emission 3 around 543 nm starts by transition to a lower state of the Tb 3+ -ions.
  • the laser emission 3 is very pronounced in this laser scheme.
  • Figure 2 shows an example for an end pumped geometry of the proposed Ce-Tb-laser.
  • the pump radiation emitted by a GaN laser diode 4 is focused by appropriate optics 5 through the first resonator end mirror 7 of the solid-state laser into the Ce 3+ -Tb 3+ co-doped gain material 6.
  • the first resonator end mirror 7 used for end pumping is highly reflective for radiation in the green wavelength region and antireflective for the pump radiation wavelength.
  • the second resonator end mirror 8 on the other hand is highly reflective for the wavelength of the pump radiation and sufficiently reflective for the green wavelength emitted by the gain material 6 in order to achieve lasing action. On the other hand this second resonator end mirror 8 allows the outcoupling of a portion of the laser emission 3 in the green wavelength region.
  • FIG 3 shows another example for the design of the proposed solid-state laser.
  • a transversally pumped geometry is used for the Ce-Tb-laser.
  • the gain medium 6 of the Ce-Tb-laser in this case has two resonator end mirrors 10 which reflect a sufficiently high portion of the generated green radiation to maintain laser action. Both resonator end mirrors 10 also serve as outcoupling mirrors for the laser radiation 3.
  • the gain medium 6 is transversally pumped by a GaN diode laser module 9 composed of several GaN laser diodes side by side in order to achieve emission of the pump radiation 1 over the whole length of the gain medium 6 as indicated in Figure 3.

Landscapes

  • Physics & Mathematics (AREA)
  • Electromagnetism (AREA)
  • Engineering & Computer Science (AREA)
  • Plasma & Fusion (AREA)
  • Optics & Photonics (AREA)
  • Lasers (AREA)
  • Semiconductor Lasers (AREA)

Abstract

L'invention concerne un laser à semi-conducteurs comprenant un milieu actif (6) constitué d'un matériau hôte à semi-conducteurs qui est co-dopé par des ions Ce3+ et des ions d'un autre matériau en terres rares. Le matériau hôte est sélectionné, de manière à ce que le bord inférieur de la cinquième bande des ions Ce3+ soit supérieur de manière énergétique à un état laser supérieur des ions de l'autre matériau en terres rares. Le laser peut être pompé de manière optique par des diodes (4) laser GaN dans la région de la longueur d'ondes comprise entre 400 et 500nm et émet un rayonnement laser dans la gamme des longueurs d'ondes visibles. Grâce à ce laser, en particulier, un laser à semi-conducteurs pompé par un laser à diode GaN, émettant dans la région de longueurs d'ondes du vert, peut être réalisé.
EP07826745A 2006-10-24 2007-10-15 Laser à semi-conducteurs pompé de manière optique au moyen d'un milieu actif co-dopé Withdrawn EP2084792A2 (fr)

Priority Applications (1)

Application Number Priority Date Filing Date Title
EP07826745A EP2084792A2 (fr) 2006-10-24 2007-10-15 Laser à semi-conducteurs pompé de manière optique au moyen d'un milieu actif co-dopé

Applications Claiming Priority (3)

Application Number Priority Date Filing Date Title
EP06122825 2006-10-24
EP07826745A EP2084792A2 (fr) 2006-10-24 2007-10-15 Laser à semi-conducteurs pompé de manière optique au moyen d'un milieu actif co-dopé
PCT/IB2007/054188 WO2008050258A2 (fr) 2006-10-24 2007-10-15 Laser à semi-conducteurs pompé de manière optique au moyen d'un milieu actif co-dopé

Publications (1)

Publication Number Publication Date
EP2084792A2 true EP2084792A2 (fr) 2009-08-05

Family

ID=39167480

Family Applications (1)

Application Number Title Priority Date Filing Date
EP07826745A Withdrawn EP2084792A2 (fr) 2006-10-24 2007-10-15 Laser à semi-conducteurs pompé de manière optique au moyen d'un milieu actif co-dopé

Country Status (5)

Country Link
EP (1) EP2084792A2 (fr)
JP (1) JP2010507920A (fr)
CN (1) CN101529672A (fr)
TW (1) TW200830652A (fr)
WO (1) WO2008050258A2 (fr)

Families Citing this family (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP2412068A1 (fr) * 2009-03-23 2012-02-01 Koninklijke Philips Electronics N.V. Laser à solide pompé optiquement et système d'éclairage comprenant ledit laser à solide
BR112012032498A2 (pt) * 2010-06-22 2016-09-13 Koninkl Philips Electronics Nv laser para emitir luz laser na faixa de espectro visível, dispositivo de iluminação e método a laser de emissão de luz laser na faixa de espectro visível
CN102051684A (zh) * 2011-01-14 2011-05-11 中国科学院上海光学精密机械研究所 铥钬共掺铝酸钇钙激光晶体的生长方法
JPWO2014006879A1 (ja) * 2012-07-02 2016-06-02 国立大学法人北海道大学 レーザー媒質、レーザー発振装置およびレーザー発振方法

Family Cites Families (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US7197059B2 (en) * 2002-05-08 2007-03-27 Melles Griot, Inc. Short wavelength diode-pumped solid-state laser

Non-Patent Citations (1)

* Cited by examiner, † Cited by third party
Title
See references of WO2008050258A3 *

Also Published As

Publication number Publication date
JP2010507920A (ja) 2010-03-11
TW200830652A (en) 2008-07-16
CN101529672A (zh) 2009-09-09
WO2008050258A2 (fr) 2008-05-02
WO2008050258A3 (fr) 2008-06-19

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