6 Direct Femtosecond Laser Writing of Optical Waveguides …
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Fig. 6.12 Schematic rendering of the double-Y-shaped microfluidic circuit irradiation patterns and
phase-contrast microscopy images of swollen red blood cells in the microchannels fabricated with
the transverse and longitudinal writing geometries [131]
[131]. Figure 6.12 shows the schematic rendering of the double-Y-shaped microfluidic circuit irradiation patterns and phase-contrast microscopy images of swollen
red blood cells in the microchannels fabricated with the transverse and longitudinal
writing geometries [131].
6.5.6 Quantum Circuits
Quantum circuits are ideal platforms for quantum information processing. By
applying direct femtosecond laser writing of glass (e.g., fused silica), 3D chip-scale
devices containing designed waveguide structures have been fabricated to realize
some functions, such as quantum computing and random walk [13]. One of the
advantages of laser-written quantum circuits is the good overlap of single-mode
fiber and waveguide channels, enabling high coupling efficiency of the devices. In
addition, the 3D devices by laser writing utilize the bulk space, which leads to much
compact design of the circuits. To date, there have been a number of applications
based on laser-written glass waveguide wafers [132, 133]. A qubit (quantum bit)
is the basic element of quantum information science, which can exist in superposition state of bit “0” and “1”. Encoding a qubit by photons can be performed in
the quantum chips by polarization or spatial mode encoding. This requires a set
of low-loss waveguide channels with sufficient coupling effect of modal profiles,
205
Fig. 6.12 Schematic rendering of the double-Y-shaped microfluidic circuit irradiation patterns and
phase-contrast microscopy images of swollen red blood cells in the microchannels fabricated with
the transverse and longitudinal writing geometries [131]
[131]. Figure 6.12 shows the schematic rendering of the double-Y-shaped microfluidic circuit irradiation patterns and phase-contrast microscopy images of swollen
red blood cells in the microchannels fabricated with the transverse and longitudinal
writing geometries [131].
6.5.6 Quantum Circuits
Quantum circuits are ideal platforms for quantum information processing. By
applying direct femtosecond laser writing of glass (e.g., fused silica), 3D chip-scale
devices containing designed waveguide structures have been fabricated to realize
some functions, such as quantum computing and random walk [13]. One of the
advantages of laser-written quantum circuits is the good overlap of single-mode
fiber and waveguide channels, enabling high coupling efficiency of the devices. In
addition, the 3D devices by laser writing utilize the bulk space, which leads to much
compact design of the circuits. To date, there have been a number of applications
based on laser-written glass waveguide wafers [132, 133]. A qubit (quantum bit)
is the basic element of quantum information science, which can exist in superposition state of bit “0” and “1”. Encoding a qubit by photons can be performed in
the quantum chips by polarization or spatial mode encoding. This requires a set
of low-loss waveguide channels with sufficient coupling effect of modal profiles,