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Magnetic-free non-reciprocity based on staggered commutation.

Reiskarimian N, Krishnaswamy H - Nat Commun (2016)

Bottom Line: However, they are typically bulky, expensive and not suitable for insertion in a conventional integrated circuit.Commutation is a form of parametric modulation with very high modulation ratio.We observe that staggered commutation enables time-reversal symmetry breaking within very small dimensions (λ/1,250 × λ/1,250 in our device), resulting in a miniature radio-frequency circulator that exhibits reduced implementation complexity, very low loss, strong non-reciprocity, significantly enhanced linearity and real-time reconfigurability, and is integrated in a conventional complementary metal-oxide-semiconductor integrated circuit for the first time.

View Article: PubMed Central - PubMed

Affiliation: Department of Electrical Engineering, Columbia University, 1300 South West Mudd, 500 West 120th Street, New York, New York 10027, USA.

ABSTRACT
Lorentz reciprocity is a fundamental characteristic of the vast majority of electronic and photonic structures. However, non-reciprocal components such as isolators, circulators and gyrators enable new applications ranging from radio frequencies to optical frequencies, including full-duplex wireless communication and on-chip all-optical information processing. Such components today dominantly rely on the phenomenon of Faraday rotation in magneto-optic materials. However, they are typically bulky, expensive and not suitable for insertion in a conventional integrated circuit. Here we demonstrate magnetic-free linear passive non-reciprocity based on the concept of staggered commutation. Commutation is a form of parametric modulation with very high modulation ratio. We observe that staggered commutation enables time-reversal symmetry breaking within very small dimensions (λ/1,250 × λ/1,250 in our device), resulting in a miniature radio-frequency circulator that exhibits reduced implementation complexity, very low loss, strong non-reciprocity, significantly enhanced linearity and real-time reconfigurability, and is integrated in a conventional complementary metal-oxide-semiconductor integrated circuit for the first time.

No MeSH data available.


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Experimental evidence of reconfigurability and enhanced linearity to port 1 excitations.(a) The direction of circulation can be altered by changing the staggering between +90° and −90°. (b) The frequency of operation of the circulator can be tuned by changing the commutation frequency within the limits dictated by the bandwidth of the 3λ/4 transmission-line ring. Here we present the non-reciprocity in S31 across different commutation frequencies ranging from 700 to 800 MHz. In each case, tuning of the port 2 impedance is exploited to achieve 40–50 dB isolation at the commutation frequency. (c) Measured two-tone linearity for transmission from port 1 to port 2 and from port 2 to port 3 are shown when configured for clockwise circulation. Nonlinear systems exhibit intermodulation distortion products when excited with two sinusoidal signals. The input-referred third-order intercept point (IIP3) represents the (extrapolated) input power of each of the two tones at which the third-order intermodulation products (IM3) at the output are as powerful as the fundamental signals. The IIP3 for transmission from port 1 to port 2 is +27.5 dBm (≈560 mW), nearly two orders of magnitude higher than that from port 2 to port 3 (+8.7 dBm or 7.4 mW), owing to the suppression of the signal across the point parametric modulator for port 1 excitations.
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f8: Experimental evidence of reconfigurability and enhanced linearity to port 1 excitations.(a) The direction of circulation can be altered by changing the staggering between +90° and −90°. (b) The frequency of operation of the circulator can be tuned by changing the commutation frequency within the limits dictated by the bandwidth of the 3λ/4 transmission-line ring. Here we present the non-reciprocity in S31 across different commutation frequencies ranging from 700 to 800 MHz. In each case, tuning of the port 2 impedance is exploited to achieve 40–50 dB isolation at the commutation frequency. (c) Measured two-tone linearity for transmission from port 1 to port 2 and from port 2 to port 3 are shown when configured for clockwise circulation. Nonlinear systems exhibit intermodulation distortion products when excited with two sinusoidal signals. The input-referred third-order intercept point (IIP3) represents the (extrapolated) input power of each of the two tones at which the third-order intermodulation products (IM3) at the output are as powerful as the fundamental signals. The IIP3 for transmission from port 1 to port 2 is +27.5 dBm (≈560 mW), nearly two orders of magnitude higher than that from port 2 to port 3 (+8.7 dBm or 7.4 mW), owing to the suppression of the signal across the point parametric modulator for port 1 excitations.

Mentions: Another unique feature of the fabricated prototype is its real-time reconfigurability. By changing the staggering between +90° and −90°, the direction of circulation can be altered, as is seen in Fig. 8a. The frequency of operation of the circulator can also be tuned by changing the frequency of commutation within the limits dictated by the bandwidth of the 3λ/4 transmission line ring. In Fig. 8b, four to five orders of magnitude (40–50 dB) of non-reciprocity in S31 is maintained across 700–800 MHz.


Magnetic-free non-reciprocity based on staggered commutation.

Reiskarimian N, Krishnaswamy H - Nat Commun (2016)

Experimental evidence of reconfigurability and enhanced linearity to port 1 excitations.(a) The direction of circulation can be altered by changing the staggering between +90° and −90°. (b) The frequency of operation of the circulator can be tuned by changing the commutation frequency within the limits dictated by the bandwidth of the 3λ/4 transmission-line ring. Here we present the non-reciprocity in S31 across different commutation frequencies ranging from 700 to 800 MHz. In each case, tuning of the port 2 impedance is exploited to achieve 40–50 dB isolation at the commutation frequency. (c) Measured two-tone linearity for transmission from port 1 to port 2 and from port 2 to port 3 are shown when configured for clockwise circulation. Nonlinear systems exhibit intermodulation distortion products when excited with two sinusoidal signals. The input-referred third-order intercept point (IIP3) represents the (extrapolated) input power of each of the two tones at which the third-order intermodulation products (IM3) at the output are as powerful as the fundamental signals. The IIP3 for transmission from port 1 to port 2 is +27.5 dBm (≈560 mW), nearly two orders of magnitude higher than that from port 2 to port 3 (+8.7 dBm or 7.4 mW), owing to the suppression of the signal across the point parametric modulator for port 1 excitations.
© Copyright Policy - open-access
Related In: Results  -  Collection

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getmorefigures.php?uid=PMC4835534&req=5

f8: Experimental evidence of reconfigurability and enhanced linearity to port 1 excitations.(a) The direction of circulation can be altered by changing the staggering between +90° and −90°. (b) The frequency of operation of the circulator can be tuned by changing the commutation frequency within the limits dictated by the bandwidth of the 3λ/4 transmission-line ring. Here we present the non-reciprocity in S31 across different commutation frequencies ranging from 700 to 800 MHz. In each case, tuning of the port 2 impedance is exploited to achieve 40–50 dB isolation at the commutation frequency. (c) Measured two-tone linearity for transmission from port 1 to port 2 and from port 2 to port 3 are shown when configured for clockwise circulation. Nonlinear systems exhibit intermodulation distortion products when excited with two sinusoidal signals. The input-referred third-order intercept point (IIP3) represents the (extrapolated) input power of each of the two tones at which the third-order intermodulation products (IM3) at the output are as powerful as the fundamental signals. The IIP3 for transmission from port 1 to port 2 is +27.5 dBm (≈560 mW), nearly two orders of magnitude higher than that from port 2 to port 3 (+8.7 dBm or 7.4 mW), owing to the suppression of the signal across the point parametric modulator for port 1 excitations.
Mentions: Another unique feature of the fabricated prototype is its real-time reconfigurability. By changing the staggering between +90° and −90°, the direction of circulation can be altered, as is seen in Fig. 8a. The frequency of operation of the circulator can also be tuned by changing the frequency of commutation within the limits dictated by the bandwidth of the 3λ/4 transmission line ring. In Fig. 8b, four to five orders of magnitude (40–50 dB) of non-reciprocity in S31 is maintained across 700–800 MHz.

Bottom Line: However, they are typically bulky, expensive and not suitable for insertion in a conventional integrated circuit.Commutation is a form of parametric modulation with very high modulation ratio.We observe that staggered commutation enables time-reversal symmetry breaking within very small dimensions (λ/1,250 × λ/1,250 in our device), resulting in a miniature radio-frequency circulator that exhibits reduced implementation complexity, very low loss, strong non-reciprocity, significantly enhanced linearity and real-time reconfigurability, and is integrated in a conventional complementary metal-oxide-semiconductor integrated circuit for the first time.

View Article: PubMed Central - PubMed

Affiliation: Department of Electrical Engineering, Columbia University, 1300 South West Mudd, 500 West 120th Street, New York, New York 10027, USA.

ABSTRACT
Lorentz reciprocity is a fundamental characteristic of the vast majority of electronic and photonic structures. However, non-reciprocal components such as isolators, circulators and gyrators enable new applications ranging from radio frequencies to optical frequencies, including full-duplex wireless communication and on-chip all-optical information processing. Such components today dominantly rely on the phenomenon of Faraday rotation in magneto-optic materials. However, they are typically bulky, expensive and not suitable for insertion in a conventional integrated circuit. Here we demonstrate magnetic-free linear passive non-reciprocity based on the concept of staggered commutation. Commutation is a form of parametric modulation with very high modulation ratio. We observe that staggered commutation enables time-reversal symmetry breaking within very small dimensions (λ/1,250 × λ/1,250 in our device), resulting in a miniature radio-frequency circulator that exhibits reduced implementation complexity, very low loss, strong non-reciprocity, significantly enhanced linearity and real-time reconfigurability, and is integrated in a conventional complementary metal-oxide-semiconductor integrated circuit for the first time.

No MeSH data available.


Related in: MedlinePlus