(a) Schematic diagram of the standrad TS-CVQKD. (b)Schematic diagram of the HLA-involved TS-CVQKD. (c) Phase space representation of thermal state. As the frequency goes down from infrared regime to microwave regime, thermal noise would be enhanced. (d) Schematic of HLA achieved with a feed-forward loop. EOM, electro-optic modulator.