Barium strontium titanate

Subramanyam, G, F.A Miranda, R.R Romanofksy, F.W Van Keuls, C.L Canedy, S Aggarwal, T Venkatesan, and Ramamoorthy Ramesh. "Ferroelectric tunable microstrip Lange coupler for K-band applications." IEEE MTT-S International Microwave Symposium Digest. Vol. 3. 2000. 1363–1366.

Subramanyam, G, F.A Miranda, F Van Keuls, R.R Romanofsky, C.L Canedy, S Aggarwal, T Venkatesan, and Ramamoorthy Ramesh. "Performance of a K-Band Voltage-Controlled Lange Coupler Using a Ferroelectric Tunable Microstrip Configuration." IEEE Microwave and Guided Wave Letters 10 (2000) 136–138.

Subramanyam, G, F.W Van Keuls, F.A Miranda, C.L Canedy, S Aggarwal, T Venkatesan, and Ramamoorthy Ramesh. "Correlation of electric field and critical design parameters for ferroelectric tunable microwave filters." Integrated Ferroelectrics. Vol. 24. Gordon & Breach Science Publ Inc, Newark, 1999. 273–285.

Van Keuls, F.W, R.R Romanofsky, N.D Varaljay, F.A Miranda, C.L Canedy, S Aggarwal, T Venkatesan, and Ramamoorthy Ramesh. "A Ku-band gold/BaxSr1-xTiO3/LaAlO3 conductor/thin-film ferroelectric microstrip line phase shifter for room-temperature communications applications." Microwave and Optical Technology Letters 20 (1999) 53–56.