The high emission density is the feature of the high-Q devices on the base of such
a diffraction grating at 10
6 Q-factor. Owing to this, the emission power, which is
entered in such a device, is limited by the extreme power of nonlinear effect
appearance. Resonators in the form of disks have the similar restriction.
The high power density applies a series of restrictions at utilization of high-Q
optical resonators and discriminators in order to implement the ultra-miniature
devices. This leads to the fact that we can only use resonators and discriminators
on the “linear” mode as discriminators, which are in the feedback loops, and at input
of which a part of the power applies from the total power acting in the main optical
channel of OEO.
As at small sizes of such a resonator (the disk radius is 1 mm and the cross-section
area of the light-guiding layer is 10
2 (μm)
2 ) and at the relatively high Q-factor of
order Q ¼ 10
7 (the equivalent length is 2 m), nonlinear effects begin to become
apparent at entry power of the order several microwatt. That is why, we can attribute
the solution search in micro-miniaturization of the linear RF FODL to promising
methods of miniature resonator implementation. For instance, at fiber length in
several kilometers, at wavelength 1.55 μm, the threshold power is about
100–200 mW.
Fig. 2.8 Stages of a technological cycle for creation of the quantum-dimension laser diode with
application of high-Q optical discriminators and resonators. (a) Creation of the diffraction grating
on the substrate, (b) obtaining of the optical discriminator (a resonator), (c) combination of the laser
and the resonator, (d) the finished laser
Fig. 2.9 Enlarged images
of the primary “mask” on
the substrate (a) and after
technological cycle of the
dry deposition of the
diffraction grating of the
discriminator optical
resonator (b) with a grating
half-period of 100 hm. The
image is enlarged with the
help of the electronic
microscope
42
2 Nanostructural Optoelectronic Oscillators with the Fiber-Optical Delay Line
a diffraction grating at 10
6 Q-factor. Owing to this, the emission power, which is
entered in such a device, is limited by the extreme power of nonlinear effect
appearance. Resonators in the form of disks have the similar restriction.
The high power density applies a series of restrictions at utilization of high-Q
optical resonators and discriminators in order to implement the ultra-miniature
devices. This leads to the fact that we can only use resonators and discriminators
on the “linear” mode as discriminators, which are in the feedback loops, and at input
of which a part of the power applies from the total power acting in the main optical
channel of OEO.
As at small sizes of such a resonator (the disk radius is 1 mm and the cross-section
area of the light-guiding layer is 10
2 (μm)
2 ) and at the relatively high Q-factor of
order Q ¼ 10
7 (the equivalent length is 2 m), nonlinear effects begin to become
apparent at entry power of the order several microwatt. That is why, we can attribute
the solution search in micro-miniaturization of the linear RF FODL to promising
methods of miniature resonator implementation. For instance, at fiber length in
several kilometers, at wavelength 1.55 μm, the threshold power is about
100–200 mW.
Fig. 2.8 Stages of a technological cycle for creation of the quantum-dimension laser diode with
application of high-Q optical discriminators and resonators. (a) Creation of the diffraction grating
on the substrate, (b) obtaining of the optical discriminator (a resonator), (c) combination of the laser
and the resonator, (d) the finished laser
Fig. 2.9 Enlarged images
of the primary “mask” on
the substrate (a) and after
technological cycle of the
dry deposition of the
diffraction grating of the
discriminator optical
resonator (b) with a grating
half-period of 100 hm. The
image is enlarged with the
help of the electronic
microscope
42
2 Nanostructural Optoelectronic Oscillators with the Fiber-Optical Delay Line