title: Passband-shifting filters through postgrowth modification of filter optical thickness.
abstract: We describe a postgrowth method to produce passband filters with different center wavelengths from a single growth run by irreversibly changing the refractive index of a layer or a series of layers within the filter. This leads to a new type of filter, the passband-shifting filter, whose center wavelength can be irreversibly shifted from lambda0 to lambda0 - deltalambda after the filter has been grown. The passband shift can be controlled exactly by proper design of the multilayer. We present the theory behind passband-shifting-filter design along with transfer-matrix simulations and preliminary experimental results for a two-cavity filter, using lateral oxidation of AlxGa1-x As-based materials to effect the passband shift.
authors.affiliation: Lincoln Laboratory, Massachusetts Institute of Technology, 244 Wood Street, Lexington, Massachusetts 01775, USA. rpatel@ll.mit.edu
authors.forename: Rajesh R
authors.initials: RR
authors.lastname: Patel
authors.forename: Denise M
authors.initials: DM
authors.lastname: Krol
authors.forename: Steven W
authors.initials: SW
authors.lastname: Bond
authors.forename: Michael D
authors.initials: MD
authors.lastname: Pocha
authors.forename: Glenn A
authors.initials: GA
authors.lastname: Meyer
authors.forename: Elaine
authors.initials: E
authors.lastname: Behymer
authors.forename: Victor
authors.initials: V
authors.lastname: Sperry