The name is absent

0.2        0.4        0.6        0.8         1

Frequency (THz)

(a) Terahertz polarization perpendicular (b) Terahertz polarization parallel

Figure 5.7 : Frequency-dependent terahertz transmission amplitude for a typical ter-
ahertz SLM pixel at various reverse gate biases for terahertz polarization (a) parallel
to and (b) perpendicular to the connecting wires. Maximum modulation observed is
25% at 0.42 THz in (a) and is 20% at 0.37 THz in (b).

modulation appear as bright image pixels. In both SLM 1 and SLM 2, some SLM
pixels are broken (incapable of modulation).

5.6 Discussion

The first-generation THz SLM design, a 4-by-4 pixel array, successfully demonstrates
a high modulation depth at the resonant frequency, uniformly across all and a negligi-
ble amount of crosstalk among pixels. Demonstratd by the interference patterns with
a double slit configuration, the kHz-rate operation of this spatial modulator reveals
great promise of its application to the single-pixel THz imaging system in Chapter 4.
The THz SLM also operates at low voltages at room temperature and with low power
consumption.

However, the characterization results of the second-generation THz SLM are not
as satisfactory as the first-generation THz SLM. The circuit board of the second-

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