Pub Date : 2000-09-25DOI: 10.1109/ISLC.2000.882318
P. Smowton, G. Lewis, P. Blood, W. Chow, S. Koch
GaInP quantum well lasers are important for applications such as DVD and photodynamic therapy. The performance of these lasers remains limited by non-radiative and carrier-leakage losses and to design fully optimised devices it is necessary to describe these losses accurately. The paper provides a quantitative analysis of these non-radiative losses through detailed comparison of experimental gain and spontaneous emission spectra with a verified theoretical model. We find that, even in the absence of carrier leakage, there is a substantial contribution to the room temperature threshold current from non-radiative recombination within the wells themselves.
{"title":"Extraction of non-radiative and carrier leakage losses in GaInP lasers through comparison of experimental and theoretical optical properties","authors":"P. Smowton, G. Lewis, P. Blood, W. Chow, S. Koch","doi":"10.1109/ISLC.2000.882318","DOIUrl":"https://doi.org/10.1109/ISLC.2000.882318","url":null,"abstract":"GaInP quantum well lasers are important for applications such as DVD and photodynamic therapy. The performance of these lasers remains limited by non-radiative and carrier-leakage losses and to design fully optimised devices it is necessary to describe these losses accurately. The paper provides a quantitative analysis of these non-radiative losses through detailed comparison of experimental gain and spontaneous emission spectra with a verified theoretical model. We find that, even in the absence of carrier leakage, there is a substantial contribution to the room temperature threshold current from non-radiative recombination within the wells themselves.","PeriodicalId":322366,"journal":{"name":"Conference Digest. 2000 IEEE 17th International Semiconductor Laser Conference. (Cat. No.00CH37092)","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2000-09-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129643638","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2000-09-25DOI: 10.1109/ISLC.2000.882305
C. Chang, L. Chrostowski, C. Chang-Hasnain
VCSELs are promising high-speed transmitters in lightwave communication systems. Two major device structures used today are oxide-confined and proton-implanted VCSELs. The former has a high capacitance due to the thin oxide layer, whereas the latter has a high resistance due to a small injection area. Oxide plus implant VCSELs was demonstrated to have >20 GHz modulation bandwidth. However, the design rule and trade-off on oxide and implant dimensions and their impact on VCSEL's modulation response have not been clearly shown. In the paper, we fabricated VCSELs of oxide-only and oxide-implant structures on the same sample and show that, conclusively and quantitatively, the additional implant process increases VCSEL modulation speed. A model is proposed to design high-speed VCSELs by removing the parasitic limitation.
{"title":"Parasitics and design considerations on oxide-implant VCSELs","authors":"C. Chang, L. Chrostowski, C. Chang-Hasnain","doi":"10.1109/ISLC.2000.882305","DOIUrl":"https://doi.org/10.1109/ISLC.2000.882305","url":null,"abstract":"VCSELs are promising high-speed transmitters in lightwave communication systems. Two major device structures used today are oxide-confined and proton-implanted VCSELs. The former has a high capacitance due to the thin oxide layer, whereas the latter has a high resistance due to a small injection area. Oxide plus implant VCSELs was demonstrated to have >20 GHz modulation bandwidth. However, the design rule and trade-off on oxide and implant dimensions and their impact on VCSEL's modulation response have not been clearly shown. In the paper, we fabricated VCSELs of oxide-only and oxide-implant structures on the same sample and show that, conclusively and quantitatively, the additional implant process increases VCSEL modulation speed. A model is proposed to design high-speed VCSELs by removing the parasitic limitation.","PeriodicalId":322366,"journal":{"name":"Conference Digest. 2000 IEEE 17th International Semiconductor Laser Conference. (Cat. No.00CH37092)","volume":"207 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2000-09-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114313966","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2000-09-25DOI: 10.1109/ISLC.2000.882317
W. Susaki, K. Kondo, H. Yaku, H. Asano, T. Fukunaga, T. Hayakawa
The hole confinement at threshold on indium content in strain-compensated (In/sub x/Ga/sub 1-x/As/GaAs/sub 0.2/P/sub 0.8/)/GaAs SQW lasers is investigated by rate equation analysis of the lasing delay time. It is shown that the temperature insensitive threshold current in these lasers is due to complete hole confinement in HH (heavy hole) band due to larger energy difference between HH and LH (light hole) bands by the excellent strain-compensated configuration. The spontaneous recombination lifetime increases with x. A temperature insensitive lifetime (8.5 ns) is observed between 20 and 8/spl deg/C for x=0.3.
{"title":"Hole confinement in strain-compensated-SQW (In/sub x/Ga/sub 1-x/As/GaAsP)/GaAs lasers","authors":"W. Susaki, K. Kondo, H. Yaku, H. Asano, T. Fukunaga, T. Hayakawa","doi":"10.1109/ISLC.2000.882317","DOIUrl":"https://doi.org/10.1109/ISLC.2000.882317","url":null,"abstract":"The hole confinement at threshold on indium content in strain-compensated (In/sub x/Ga/sub 1-x/As/GaAs/sub 0.2/P/sub 0.8/)/GaAs SQW lasers is investigated by rate equation analysis of the lasing delay time. It is shown that the temperature insensitive threshold current in these lasers is due to complete hole confinement in HH (heavy hole) band due to larger energy difference between HH and LH (light hole) bands by the excellent strain-compensated configuration. The spontaneous recombination lifetime increases with x. A temperature insensitive lifetime (8.5 ns) is observed between 20 and 8/spl deg/C for x=0.3.","PeriodicalId":322366,"journal":{"name":"Conference Digest. 2000 IEEE 17th International Semiconductor Laser Conference. (Cat. No.00CH37092)","volume":"21 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2000-09-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121944493","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2000-09-25DOI: 10.1109/ISLC.2000.882287
K. Choquette, A. Fischer, K. Geib, G. R. Hadley, A. Allerman, J. J. Hindi
The modal discrimination can be augmented by creating a central region of gain surrounded by a region of optical loss. We report single mode output of more than 5 mW for 850 nm VCSELs fabricated using a hybrid ion implantation and selective oxidation device structure designed to achieve this end.
{"title":"High single mode operation from hybrid ion implanted/selectively oxidized VCSELs","authors":"K. Choquette, A. Fischer, K. Geib, G. R. Hadley, A. Allerman, J. J. Hindi","doi":"10.1109/ISLC.2000.882287","DOIUrl":"https://doi.org/10.1109/ISLC.2000.882287","url":null,"abstract":"The modal discrimination can be augmented by creating a central region of gain surrounded by a region of optical loss. We report single mode output of more than 5 mW for 850 nm VCSELs fabricated using a hybrid ion implantation and selective oxidation device structure designed to achieve this end.","PeriodicalId":322366,"journal":{"name":"Conference Digest. 2000 IEEE 17th International Semiconductor Laser Conference. (Cat. No.00CH37092)","volume":"73 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2000-09-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124265052","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2000-09-25DOI: 10.1109/ISLC.2000.882293
F. Koyama, D. Schlenker, T. Miyamoto, Z. Chen, T. Yamatoya, T. Kondo, K. Iga
Presents the high power operation of a tapered superluminescent diode with highly strained GaInAs/GaAs QWs emitting at in the 1.2 /spl mu/m band. As its background, we achieved the wavelength extension of GaInAs/GaAs QWs beyond 1.2 /spl mu/m by using highly strained QWs. Also, we presented low threshold and excellent temperature characteristics of 1.2 /spl mu/m QW lasers, and their application for single mode fiber datacom. However, there have been difficulties in realizing high power light sources in the wavelength range of 1.1-1.2 /spl mu/m. They may open up new applications, which include pumping for 1.2-1.3 /spl mu/m Raman fiber amplifiers, free-space LANs and so on.
{"title":"1.5 W operation of superluminescent diode with highly strained GaInAs/GaAs quantum well emitting at 1.2 /spl mu/m band","authors":"F. Koyama, D. Schlenker, T. Miyamoto, Z. Chen, T. Yamatoya, T. Kondo, K. Iga","doi":"10.1109/ISLC.2000.882293","DOIUrl":"https://doi.org/10.1109/ISLC.2000.882293","url":null,"abstract":"Presents the high power operation of a tapered superluminescent diode with highly strained GaInAs/GaAs QWs emitting at in the 1.2 /spl mu/m band. As its background, we achieved the wavelength extension of GaInAs/GaAs QWs beyond 1.2 /spl mu/m by using highly strained QWs. Also, we presented low threshold and excellent temperature characteristics of 1.2 /spl mu/m QW lasers, and their application for single mode fiber datacom. However, there have been difficulties in realizing high power light sources in the wavelength range of 1.1-1.2 /spl mu/m. They may open up new applications, which include pumping for 1.2-1.3 /spl mu/m Raman fiber amplifiers, free-space LANs and so on.","PeriodicalId":322366,"journal":{"name":"Conference Digest. 2000 IEEE 17th International Semiconductor Laser Conference. (Cat. No.00CH37092)","volume":"116 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2000-09-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"117232816","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2000-09-25DOI: 10.1109/ISLC.2000.882325
P. Varangis, H. Li, G.T. Liu, T. Newell, A. Stintz, B. Fuchs, K. Malloy, L. Lester
We report on the 183 nm tuning range of an anti-reflection coated quantum dot (QD) laser using a diffraction grating in an external-cavity configuration. Over this range the laser threshold current density varied between 0.25 kA/cm/sup 2/ and 2.22 kA/cm/sup 2/ with an average value of 0.84 kA/cm/sup 2/. The laser active region is composed of a single InAs quantum dot layer confined in the middle of a 10-nm thick InGaAs quantum well and sandwiched by GaAs waveguide layers.
{"title":"183 nm tuning range in a grating-coupled external-cavity quantum dot laser","authors":"P. Varangis, H. Li, G.T. Liu, T. Newell, A. Stintz, B. Fuchs, K. Malloy, L. Lester","doi":"10.1109/ISLC.2000.882325","DOIUrl":"https://doi.org/10.1109/ISLC.2000.882325","url":null,"abstract":"We report on the 183 nm tuning range of an anti-reflection coated quantum dot (QD) laser using a diffraction grating in an external-cavity configuration. Over this range the laser threshold current density varied between 0.25 kA/cm/sup 2/ and 2.22 kA/cm/sup 2/ with an average value of 0.84 kA/cm/sup 2/. The laser active region is composed of a single InAs quantum dot layer confined in the middle of a 10-nm thick InGaAs quantum well and sandwiched by GaAs waveguide layers.","PeriodicalId":322366,"journal":{"name":"Conference Digest. 2000 IEEE 17th International Semiconductor Laser Conference. (Cat. No.00CH37092)","volume":"80 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2000-09-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133317508","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2000-09-25DOI: 10.1109/ISLC.2000.882280
N. Nunoya, M. Morshed, M. Nakamura, S. Tamura, S. Arai
We demonstrated low threshold current and stable single-mode operation of 1.55 μm wavelength GaInAsP-InP BH-DFB lasers with periodic wirelike active regions by adopting a gain-matching effect in strongly index-coupled structure.
{"title":"High single-mode yield 1.55 /spl mu/m GaInAsP/InP BH-DFB lasers with periodic wirelike active regions","authors":"N. Nunoya, M. Morshed, M. Nakamura, S. Tamura, S. Arai","doi":"10.1109/ISLC.2000.882280","DOIUrl":"https://doi.org/10.1109/ISLC.2000.882280","url":null,"abstract":"We demonstrated low threshold current and stable single-mode operation of 1.55 μm wavelength GaInAsP-InP BH-DFB lasers with periodic wirelike active regions by adopting a gain-matching effect in strongly index-coupled structure.","PeriodicalId":322366,"journal":{"name":"Conference Digest. 2000 IEEE 17th International Semiconductor Laser Conference. (Cat. No.00CH37092)","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2000-09-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115742286","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2000-09-25DOI: 10.1109/ISLC.2000.882267
C. Carlsson, H. Martinsson, J. Vukusic, J. Halonen, A. Larsson
Vertical cavity surface emitting lasers (VCSELs) are attractive for fiber optical distribution of RF-signals in cost sensitive applications such as intra-building antenna remoting in wireless networks. VCSELs emitting at 850 nm, together with low modal dispersion multimode fibers, are expected to provide adequate performance for such applications over distances of the order of 100 meters. VCSELs emitting at 650 nm, together with graded index plastic optical fiber (POF), may offer the ultimate low cost solution for shorter distance transmission of the analog signals. For this purpose we have fabricated GaAs-based oxide confined VCSELs with an InGaP/InGaAlP MQW active region for emission at 670 nm and characterized their analog modulation properties in the frequency range 0.1-3 GHz using two-tone measurements.
{"title":"Analog modulation performance of red (670 nm) oxide confined VCSELs","authors":"C. Carlsson, H. Martinsson, J. Vukusic, J. Halonen, A. Larsson","doi":"10.1109/ISLC.2000.882267","DOIUrl":"https://doi.org/10.1109/ISLC.2000.882267","url":null,"abstract":"Vertical cavity surface emitting lasers (VCSELs) are attractive for fiber optical distribution of RF-signals in cost sensitive applications such as intra-building antenna remoting in wireless networks. VCSELs emitting at 850 nm, together with low modal dispersion multimode fibers, are expected to provide adequate performance for such applications over distances of the order of 100 meters. VCSELs emitting at 650 nm, together with graded index plastic optical fiber (POF), may offer the ultimate low cost solution for shorter distance transmission of the analog signals. For this purpose we have fabricated GaAs-based oxide confined VCSELs with an InGaP/InGaAlP MQW active region for emission at 670 nm and characterized their analog modulation properties in the frequency range 0.1-3 GHz using two-tone measurements.","PeriodicalId":322366,"journal":{"name":"Conference Digest. 2000 IEEE 17th International Semiconductor Laser Conference. (Cat. No.00CH37092)","volume":"27 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2000-09-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125574981","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2000-09-25DOI: 10.1109/ISLC.2000.882328
M. Mohrle, B. Sartorius, S. Bauer, O. Brox, A. Sigmund, R. Steingruber, M. Radziunas, H. Wunsche
InGaAsP multisection-DFB-lasers with detuned gratings have been fabricated. Self-pulsation in the 40GHz range and the locking to data signals is demonstrated. Even higher self pulsation frequencies can be obtained based on the new concept.
{"title":"Detuned grating multi-section-RW-DFB-lasers for high speed optical signal processing","authors":"M. Mohrle, B. Sartorius, S. Bauer, O. Brox, A. Sigmund, R. Steingruber, M. Radziunas, H. Wunsche","doi":"10.1109/ISLC.2000.882328","DOIUrl":"https://doi.org/10.1109/ISLC.2000.882328","url":null,"abstract":"InGaAsP multisection-DFB-lasers with detuned gratings have been fabricated. Self-pulsation in the 40GHz range and the locking to data signals is demonstrated. Even higher self pulsation frequencies can be obtained based on the new concept.","PeriodicalId":322366,"journal":{"name":"Conference Digest. 2000 IEEE 17th International Semiconductor Laser Conference. (Cat. No.00CH37092)","volume":"35 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2000-09-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131201923","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2000-09-25DOI: 10.1109/ISLC.2000.882321
W. Bewley, C. L. Felix, I. Vurgaftman, R. Bartolo, D. Stokes, M. Jurkovic, J. Lindle, J. R. Meyer, M. Yang, H. Lee, R. Menna, R. Martinelli, D. Garbuzov, J. Connolly, M. Maiorov, A. Sugg, G. Olsen
There is a growing demand for midwave-infrared (3-5 /spl mu/m) laser diodes operating in CW mode at non-cryogenic temperatures, for chemical sensing and other applications requiring low cost and portability. While optically-pumped mid-IR "W" lasers recently achieved CW operation up to 290 K, previous III-V diodes emitting beyond 3 /spl mu/m have never operated CW above 180 K. In the presentation we report progress toward the goal of thermoelectrically (TE) cooled operation by using antimonide type-II W quantum well (QW) diodes, and also high-power/high-brightness using optically-pumped angled-grating distributed feedback (/spl alpha/-DFB) lasers with W active regions. The InAs(l5/spl Aring/)/Ga/sub 0.75/In/sub 0.25/Sb(27/spl Aring/)/InAs(15/spl Aring/)/AlGaAsSb(80/spl Aring/) W diode active region is designed to rely on light holes for the interwell tunneling transport rather than heavy holes. Another key design element is the insertion of relatively thick (0.6 /spl mu/m-thick) undoped AlGaAsSb separate confinement heterostructure (SCH) layers on each side of the active region. By increasing the mode overlap with the waveguide core, this "broadened waveguide" configuration maximizes the optical confinement factor in the active region with 5 or 10 quantum wells while minimizing free-carrier absorption losses in the doped AlGaAsSb cladding layers.
{"title":"Mid-IR broadened-waveguide and angled-grating distributed feedback (/spl alpha/-DFB) \"W\" quantum well lasers","authors":"W. Bewley, C. L. Felix, I. Vurgaftman, R. Bartolo, D. Stokes, M. Jurkovic, J. Lindle, J. R. Meyer, M. Yang, H. Lee, R. Menna, R. Martinelli, D. Garbuzov, J. Connolly, M. Maiorov, A. Sugg, G. Olsen","doi":"10.1109/ISLC.2000.882321","DOIUrl":"https://doi.org/10.1109/ISLC.2000.882321","url":null,"abstract":"There is a growing demand for midwave-infrared (3-5 /spl mu/m) laser diodes operating in CW mode at non-cryogenic temperatures, for chemical sensing and other applications requiring low cost and portability. While optically-pumped mid-IR \"W\" lasers recently achieved CW operation up to 290 K, previous III-V diodes emitting beyond 3 /spl mu/m have never operated CW above 180 K. In the presentation we report progress toward the goal of thermoelectrically (TE) cooled operation by using antimonide type-II W quantum well (QW) diodes, and also high-power/high-brightness using optically-pumped angled-grating distributed feedback (/spl alpha/-DFB) lasers with W active regions. The InAs(l5/spl Aring/)/Ga/sub 0.75/In/sub 0.25/Sb(27/spl Aring/)/InAs(15/spl Aring/)/AlGaAsSb(80/spl Aring/) W diode active region is designed to rely on light holes for the interwell tunneling transport rather than heavy holes. Another key design element is the insertion of relatively thick (0.6 /spl mu/m-thick) undoped AlGaAsSb separate confinement heterostructure (SCH) layers on each side of the active region. By increasing the mode overlap with the waveguide core, this \"broadened waveguide\" configuration maximizes the optical confinement factor in the active region with 5 or 10 quantum wells while minimizing free-carrier absorption losses in the doped AlGaAsSb cladding layers.","PeriodicalId":322366,"journal":{"name":"Conference Digest. 2000 IEEE 17th International Semiconductor Laser Conference. (Cat. No.00CH37092)","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2000-09-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130667611","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
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