**7. Applications in flexible non-volatile memory and RF switch**

Applications in flexible memory devices and RF switches were investigated based on 2D memristors. The high breaking strain and ease of integration of 2D materials on soft substrates can afford flexible non-volatile memory devices that can endure mechanical cycling (**Figure 11** for MoS2-based memristor).

Non-volatile low-power RF switches represents another major application of atomristors. The low ON-state resistance values, below ~10 Ω, is critical for lowloss non-volatile RF switch circuits. The intrinsic experimental RF characteristics of monolayer MoS2 switch show promising results of ~0.3 dB insertion loss in the ON-state (**Figure 12a**) and isolation below 20 dB in the OFF-state (**Figure 12b**) at frequencies up to 50 GHz [29]. By using monolayer h-BN as the active layer in the RF switch, the device exhibits a cutoff-frequency figure of merit of around 129 THz with a low insertion loss (≤0.5 dB) and high isolation (≥10 dB) from 0.1 to 200 GHz. In addition, it shows a high-power handling (around 20 dBm) and nanosecond switching speeds, which are superior to those of existing solid-state switches [31]. This new application leads to the development of a nanoscale energy-efficient high-frequency solid-state switch technology for the rapidly growing communication systems in the 5G band and beyond.

A comparison between 2D atomristors discussed in this chapter and other representative 2D-based memory devices is presented in **Table 1**, highlighting the thinnest active layer thickness with superior switching properties and reliability as mentioned above.

**Figure 12.** *Radio-frequency characterization of the MoS2 RF switch: (a) insertion loss and (b) isolation.*


**Table 1.**

*Comparison of atomristors with other representative works in 2D memory.*

**18**
