Applied Physics B

, Volume 97, Issue 1, pp 53–60

Dispersionless saturable absorber mirrors with large modulation depths and low saturation fluences

  • M. P. Lumb
  • P. N. Stavrinou
  • E. M. Clarke
  • R. Murray
  • C. G. Leburn
  • C. Jappy
  • N. K. Metzger
  • C. T. A. Brown
  • W. Sibbett
Article

DOI: 10.1007/s00340-009-3531-y

Cite this article as:
Lumb, M.P., Stavrinou, P.N., Clarke, E.M. et al. Appl. Phys. B (2009) 97: 53. doi:10.1007/s00340-009-3531-y

Abstract

We show that it is possible to eliminate group delay dispersion over wide bandwidths in low-finesse, resonant saturable absorber mirrors, whilst maintaining a low saturation fluence and a high modulation depth. By modelling the mirror structure we demonstrate that these properties can be produced by capping a resonant device with a single dielectric layer of carefully selected refractive index. We show that a specially capped dispersionless structure minimises the temporal broadening of femtosecond pulses reflected from the mirror. We compare this device against uncapped-resonant and anti-resonant structures. The superior performance of the capped, dispersionless device was verified experimentally by comparing resonant, anti-resonant and dispersionless quantum-dot (QD) saturable absorber mirrors incorporated into a Cr4+:forsterite laser system. We found that a minimum pulse duration of 86 fs could be achieved for the dispersionless structure at 1290 nm with an output power of 55 mW compared to 122 fs in an anti-resonant structure and several-picosecond pulses for a resonant structure.

PACS

42.60.Fc78.67.Pt78.67.Hc

Copyright information

© Springer-Verlag 2009

Authors and Affiliations

  • M. P. Lumb
    • 1
  • P. N. Stavrinou
    • 1
  • E. M. Clarke
    • 1
  • R. Murray
    • 1
  • C. G. Leburn
    • 2
  • C. Jappy
    • 2
  • N. K. Metzger
    • 2
  • C. T. A. Brown
    • 2
  • W. Sibbett
    • 2
  1. 1.Department of Physics, Blackett LaboratoryImperial College LondonLondonUK
  2. 2.J.F. Allen Physics Research Laboratories, School of Physics and AstronomyUniversity of St. AndrewsSt. AndrewsUK