Skip to content

Research at St Andrews

Optically-induced switching between mode-locked and unmode-locked continuous wave regimes of a femtosecond Cr4+:forsterite laser

Research output: Chapter in Book/Report/Conference proceedingConference contribution

DOI

Author(s)

D. A. Walsh, C. E. Crombie, W. Sibbett, C. T. A. Brown, V. G. Savitski, D. Burns, S. Calvez

School/Research organisations

Abstract

The ability to control the temporal output from a femtosecond laser can enable the same laser to be used for multiple functions, for example, the laser used in an optical tweezers system could be used as a constant-intensity source to trap a biological cell and then be temporarily switched to mode-locked operation to effect photoporation. Here, we report the rapid switching of a Cr4+:forsterite laser between mode-locked and unmode-locked continuous wave (CW) regimes via the optical pumping of an intracavity SESAM element. Mode-locking of the laser was initiated by an intracavity quantum well (GaInAsN) SESAM having an anti-resonant design (Delta R similar to 0.3%, lambda(PL)similar to 1310nm) that yielded transform-limited 89fs pulses centered around 1296nm with a repetition rate of 162MHz at an average power of 64mW. Upon excitation of the SESAM with 600mW of extra-cavity power from an 808nm semiconductor diode laser, switching could be induced between the unmode-locked and mode-locked regimes. Transitions free of Q-switching or relaxation oscillations were observed with <200 mu s switching times for both for the initiation and cessation of mode-locking. Periods of mode-locked operation of custom duration could be produced by appropriate control of the SESAM pump diode enabling the generation of bursts of pulses as short as 400 mu s. Switching was confirmed to originate from local pump-induced heating of the SESAM by observing the laser going through identical regime switching when the chip temperature of the 'unpumped' SESAM was raised by similar to 20 degrees C.

Close

Details

Original languageEnglish
Title of host publicationLASER SOURCES AND APPLICATIONS
EditorsT Graf, JI Mackenzie, H Jelinkova, J Powell
Place of PublicationBELLINGHAM
PublisherSPIE
Pages-
Number of pages10
ISBN (Print)978-0-8194-9125-1
DOIs
Publication statusPublished - 2012
EventConference on Laser Sources and Applications - Brussels
Duration: 16 Apr 201219 Apr 2012

Conference

ConferenceConference on Laser Sources and Applications
CityBrussels
Period16/04/1219/04/12

Discover related content
Find related publications, people, projects and more using interactive charts.

View graph of relations

Related by author

  1. Ultrafast high-repetition-rate waveguide lasers

    Shepherd, D., Choudhary, A., Lagatsky, A. A., Kannan, P., Beecher, S., Eason, R., Mackenzie, J., Feng, X., Sibbett, W. & Brown, C. T. A., Mar 2016, In : IEEE Journal of Selected Topics in Quantum Electronics. 22, 2

    Research output: Contribution to journalArticle

  2. A diode-pumped 1.5 mu m waveguide laser mode-locked at 6.8 GHz by a quantum dot SESAM

    Choudhary, A., Lagatsky, A. A., Zhang, Z. Y., Zhou, K. J., Wang, Q., Hogg, R. A., Pradeesh, K., Rafailov, E. U., Sibbett, W., Brown, C. T. A. & Shepherd, D. P., Oct 2013, In : Laser Physics Letters. 10, 10, 4 p., 105803.

    Research output: Contribution to journalArticle

  3. Fundamentally mode-locked, femtosecond waveguide oscillators with multi-gigahertz repetition frequencies up to 15 GHz

    Lagatsky, A. A., Choudhary, A., Kannan, P., Shepherd, D. P., Sibbett, W. & Brown, C. T. A., 26 Aug 2013, In : Optics Express. 21, 17, p. 19608-19614 7 p.

    Research output: Contribution to journalArticle

  4. 2 μm solid-state laser mode-locked by single-layer graphene

    Lagatsky, A. A., Sun, Z., Kulmala, T. S., Sundaram, R. S., Milana, S., Torrisi, F., Antipov, O. L., Lee, Y., Ahn, J. H., Brown, C. T. A., Sibbett, W. & Ferrari, A. C., 7 Jan 2013, In : Applied Physics Letters. 102, 1, 4 p., 013113.

    Research output: Contribution to journalArticle

  5. Diode-pumped femtosecond solid-state waveguide laser with a 4.9 GHz pulse repetition rate

    Choudhary, A., Lagatsky, A. A., Kannan, P., Sibbett, W., Brown, C. T. A. & Shepherd, D. P., 1 Nov 2012, In : Optics Letters. 37, 21, p. 4416-4418 3 p.

    Research output: Contribution to journalArticle

ID: 27075403

Top