The population trapping effect of the 3F4 level is an important factor limiting the power scaling of the 2.3 μm thulium(Tm)laser on the 3H4→3 H5 transition.In this Letter,we demonstrate a novel scheme of ground stat...The population trapping effect of the 3F4 level is an important factor limiting the power scaling of the 2.3 μm thulium(Tm)laser on the 3H4→3 H5 transition.In this Letter,we demonstrate a novel scheme of ground state absorption(GSA)(3 H6→3H4) and excited state absorption(ESA)(3F4→3H4] dual-wavelength pumped 2.3 μm Tm lasers.Introducing an ESA pumping process can accurately excite the Tm3+ ions accumulated in the 3F4 level to the 3H4 level,constructing a double populating mechanism for the upper laser level 3H4.A proof-of-principle experimental demonstration of the GSA(785 nm) and ESA(1470 nm) dual-wavelength pumped 2.3 μm Tm:LiYF4(Tm:YLF) laser was realized.A maximum continuous-wave output power of 1.84 W at 2308 nm was achieved under 785 and 1470 nm dual-wavelength pumping,increased by60% compared with the case of 785 nm single-wavelength pumping under the same resonator condition.Our work provides an efficient way to achieve higher output power from 2.3 μm Tm-doped lasers on the 3H4→3 H5 transition.展开更多
Expression of recombinant protein in Escherichia coli （E.coli） is generally considered as one of the ideal systems to produce proteins for industrial production.However,the majority of proteins usually fail to fold ...Expression of recombinant protein in Escherichia coli （E.coli） is generally considered as one of the ideal systems to produce proteins for industrial production.However,the majority of proteins usually fail to fold into their native state and accumulate as insoluble inclusion bodies with no biological activity in E.coli（Yang et al.,2003）.展开更多
基金supported by the National Natural Science Foundation of China (Nos. 61875077, 61911530131, and U1730119)the Natural Science Foundation of the Jiangsu Higher Education Institutions of China (No. 18KJA510001)the Priority Academic Program Development of Jiangsu Higher Education Institutions (PAPD)
文摘The population trapping effect of the 3F4 level is an important factor limiting the power scaling of the 2.3 μm thulium(Tm)laser on the 3H4→3 H5 transition.In this Letter,we demonstrate a novel scheme of ground state absorption(GSA)(3 H6→3H4) and excited state absorption(ESA)(3F4→3H4] dual-wavelength pumped 2.3 μm Tm lasers.Introducing an ESA pumping process can accurately excite the Tm3+ ions accumulated in the 3F4 level to the 3H4 level,constructing a double populating mechanism for the upper laser level 3H4.A proof-of-principle experimental demonstration of the GSA(785 nm) and ESA(1470 nm) dual-wavelength pumped 2.3 μm Tm:LiYF4(Tm:YLF) laser was realized.A maximum continuous-wave output power of 1.84 W at 2308 nm was achieved under 785 and 1470 nm dual-wavelength pumping,increased by60% compared with the case of 785 nm single-wavelength pumping under the same resonator condition.Our work provides an efficient way to achieve higher output power from 2.3 μm Tm-doped lasers on the 3H4→3 H5 transition.
基金supported by the grants of the National Natural Science Foundation of China(No.31070717)Tianjin International Science and Technology Cooperation Project (No.09ZCGHHZ00500)the 111 Project(No.B08011)
文摘Expression of recombinant protein in Escherichia coli （E.coli） is generally considered as one of the ideal systems to produce proteins for industrial production.However,the majority of proteins usually fail to fold into their native state and accumulate as insoluble inclusion bodies with no biological activity in E.coli（Yang et al.,2003）.
