Wideband hybrid fiber amplifiers and lasers operating in the 2000 nm wavelength region
A hybrid optical fiber amplifying device is proposed that is based upon a concatenated combination of a section of Tm-doped fiber (TDF) followed by a section of Ho-doped fiber (HDF). The doped fiber sections are configured to be no more than a few meters in length. Using the sections of doped fiber in this order (i.e., TDF followed by HDF) has been found to provide amplification of input signals over a relatively wide wavelength band from about 1725 nm to about 2105 nm (thus exhibiting a useful wideband range of about 380 nm). The use of pump beams operating at several Watts of power have been found to yield multi-Watt output signals. The wideband hybrid device itself may take the form of an amplifier, laser (including a ring laser configuration), or a source of amplified stimulated emission (ASE).
1 . A method of amplifying light using a hybrid fiber optical amplifier comprising a Tm-doped fiber amplifier (TDFA) comprising Tm-doped fiber (TDF) coupled with a source of pumping light for exciting the Tm-doped fiber, an Ho-doped fiber amplifier (HDFA) comprising Ho-doped fiber (HDF) coupled with a source of pumping light for exciting the Ho-doped fiber, and an optical coupler connecting the TDFA to the HDFA to create an optical path therethrough beginning with the TDFA and continuing through the HDFA, the method comprising:
(a) introducing light to be amplified into the pumped TDFA, then
(b) introducing the light to be amplified into the pumped HDFA
wherein the amplified light is emitted from the hybrid fiber optical amplifier after passing through the pumped HDFA.
2 . The method of claim 1 , wherein the wavelength of the pumping light for exciting the Tm-doped fiber (λTm) and the pumping light for exciting the Ho-doped fiber (λHo) are outside the wavelengths of the input light to be amplified (λI).
3 . A method of amplifying light using a hybrid fiber optical amplifier, the method comprising:
(a) introducing light to be amplified into a Tm-doped fiber amplifier (TDFA) comprising Tm-doped fiber (TDF), then
(b) introducing the light to be amplified into an Ho-doped fiber amplifier (HDFA) comprising Ho-doped fiber (HDF), then
(c) emitting amplified light from the hybrid fiber optical amplifier.
4 . The method of claim 3 , further comprising:
coupling the HDF with a source of pumping light for exciting the Ho-doped fiber.
5 . The method of claim 3 , further comprising:
coupling the TDF with a source of pumping light for exciting the Tm-doped fiber.
6 . The method of claim 3 , wherein an optical coupler connects the TDFA to the HDFA to create an optical path therethrough.