We experimentally demonstrate digital communications in the terahertz (THz) band using a rubidium vapor cell as a quantum receiver. We utilize amplitude modulation to encode digital information in THz photons, which are coherently upconverted to optical photons via a Rydberg six-wave-mixing process. We achieve a data transmission rate of up to 1.16 Mbit/s and a tunable bandwidth of up to 142 MHz near a 0.11 THz carrier. With reduced data rate and increased integration time per bit, we demonstrate weak-field THz transmission with a receiver sensitivity in the −130 dBm range. As a proof of principle, we perform an end-to-end transmission of digital color images in the THz band. Our work provides the possibility of THz communication at the single-photon level.
REFERENCES
1.
S.
Cherry
, “Edholm's law of bandwidth
,” IEEE Spectr.
41
(7
), 58
–60
(2004
).2.
H. J.
Song
and T.
Nagatsuma
, “Present and future of terahertz communications
,” IEEE Trans. Terahertz Sci. Technol.
1
(1
), 256
–263
(2011
).3.
C.
Sirtori
, “Bridge for the terahertz gap
,” Nature
417
(6885
), 132
–133
(2002
).4.
R.
Kleiner
, “Filling the terahertz gap
,” Science
318
(5854
), 1254
–1255
(2007
).5.
H.
Fan
, S.
Kumar
, J.
Sedlacek
, H.
Kübler
, S.
Karimkashi
, and J. P.
Shaffer
, “Atom based RF electric field sensing
,” J. Phys. B: At., Mol. Opt. Phys.
48
(20
), 202001
(2015
).6.
H.
Zhang
, Y.
Ma
, K.
Liao
, W.
Yang
, Z.
Liu
, D.
Ding
, H.
Yan
, W.
Li
, and L.
Zhang
, “Rydberg atom electric field sensing for metrology, communication and hybrid quantum systems
,” Sci. Bull.
69
(10
), 1515
–1535
(2024
).7.
Y. Y.
Jau
and T.
Carter
, “Vapor-cell-based atomic electrometry for detection frequencies below 1 kHz
,” Phys. Rev. Appl.
13
(5
), 054034
(2020
).8.
S. A.
Miller
, D. A.
Anderson
, and G.
Raithel
, “Radio-frequency-modulated Rydberg states in a vapor cell
,” New J. Phys.
18
(5
), 053017
(2016
).9.
C. G.
Wade
, N.
Sibalic
, N. R.
de Melo
, J. M.
Kondo
, C. S.
Adams
, and K. J.
Weatherill
, “Real-time near-field terahertz imaging with atomic optical fluorescence
,” Nat. Photonics
11
(1
), 40
–43
(2017
).10.
J. A.
Sedlacek
, A.
Schwettmann
, H.
Kübler
, R.
Löw
, T.
Pfau
, and J. P.
Shaffer
, “Microwave electrometry with Rydberg atoms in a vapour cell using bright atomic resonances
,” Nat. Phys.
8
(11
), 819
–824
(2012
).11.
D. H.
Meyer
, Z. A.
Castillo
, K. C.
Cox
, and P. D.
Kunz
, “Assessment of Rydberg atoms for wideband electric field sensing
,” J. Phys. B: At., Mol. Opt. Phys.
53
(3
), 034001
(2020
).12.
G.
Allinson
, M. J.
Jamieson
, A. R.
Mackellar
, L.
Downes
, C. S.
Adams
, and K. J.
Weatherill
, “Simultaneous multiband radio-frequency detection using high-orbital-angular-momentum states in a Rydberg-atom receiver
,” Phys. Rev. Res.
6
(2
), 023317
(2024
).13.
S.
Haroche
, “Nobel lecture: Controlling photons in a box and exploring the quantum to classical boundary
,” Rev. Mod. Phys.
85
(3
), 1083
–1102
(2013
).14.
S.
Kumar
, H.
Fan
, H.
Kübler
, J.
Sheng
, and J. P.
Shaffer
, “Atom-based sensing of weak radio frequency electric fields using homodyne readout
,” Sci. Rep.
7
(1
), 42981
(2017
).15.
S.
Kumar
, H.
Fan
, H.
Kübler
, A. J.
Jahangiri
, and J. P.
Shaffer
, “Rydberg-atom based radio-frequency electrometry using frequency modulation spectroscopy in room-temperature vapor cells
,” Opt. Express
25
(8
), 8625
–8637
(2017
).16.
H.
Fan
, S.
Kumar
, J.
Sheng
, and J. P.
Shaffer
, “Effect of vapor-cell geometry on Rydberg-atom-based measurements of radio-frequency electric fields
,” Phys. Rev. Appl.
4
(4
), 044015
(2015
).17.
J. A.
Sedlacek
, A.
Schwettmann
, H.
Kübler
, and J. P.
Shaffer
, “Atom-based vector microwave electrometry using rubidium Rydberg atoms in a vapor cell
,” Phys. Rev. Lett.
111
(6
), 063001
(2013
).18.
M.
Jing
, Y.
Hu
, J.
Ma
, H.
Zhang
, L.
Zhang
, L.
Xiao
, and S.
Jia
, “Atomic superheterodyne receiver based on microwave-dressed Rydberg spectroscopy
,” Nat. Phys.
16
(9
), 911
–915
(2020
).19.
M. T.
Simons
, A. H.
Haddab
, J. A.
Gordon
, and C. L.
Holloway
, “A Rydberg atom-based mixer: Measuring the phase of a radio frequency wave
,” Appl. Phys. Lett.
114
(11
), 114101
(2019
).20.
H. Q.
Fan
, S.
Kumar
, R.
Daschner
, H.
Kübler
, and J. P.
Shaffer
, “Subwavelength microwave electric-field imaging using Rydberg atoms inside atomic vapor cells
,” Opt. Lett.
39
(10
), 3030
–3033
(2014
).21.
C. L.
Holloway
, J. A.
Gordon
, A.
Schwarzkopf
, D. A.
Anderson
, S. A.
Miller
, N.
Thaicharoen
, and G.
Raithel
, “Sub-wavelength imaging and field mapping via electromagnetically induced transparency and Autler-Townes splitting in Rydberg atoms
,” Appl. Phys. Lett.
104
(24
), 244102
(2014
).22.
F.
Ripka
, H.
Kübler
, R.
Löw
, and T.
Pfau
, “A room-temperature single-photon source based on strongly interacting Rydberg atoms
,” Science
362
(6413
), 446
–449
(2018
).23.
S.
Shi
, B.
Xu
, K.
Zhang
, G. S.
Ye
, D. S.
Xiang
, Y.
Liu
, J.
Wang
, D.
Su
, and L.
Li
, “High-fidelity photonic quantum logic gate based on near-optimal Rydberg single-photon source
,” Nat. Commun.
13
(1
), 4454
(2022
).24.
H. T.
Tu
, K. Y.
Liao
, Z. X.
Zhang
, X. H.
Liu
, S. Y.
Zheng
, S. Z.
Yang
, X. D.
Zhang
, H.
Yan
, and S. L.
Zhu
, “High-efficiency coherent microwave-to-optics conversion via off-resonant scattering
,” Nat. Photonics
16
(4
), 291
–296
(2022
).25.
T.
Vogt
, C.
Gross
, J.
Han
, S. B.
Pal
, M.
Lam
, M.
Kiffner
, and W.
Li
, “Efficient microwave-to-optical conversion using Rydberg atoms
,” Phys. Rev. A
99
(2
), 023832
(2019
).26.
A.
Kumar
, A.
Suleymanzade
, M.
Stone
, L.
Taneja
, A.
Anferov
, D. I.
Schuster
, and J.
Simon
, “Quantum-enabled millimetre wave to optical transduction using neutral atoms
,” Nature
615
(7953
), 614
–619
(2023
).27.
H. J.
Kimble
, “The quantum internet
,” Nature
453
(7198
), 1023
–1030
(2008
).28.
S.
Wehner
, D.
Elkouss
, and R.
Hanson
, “Quantum internet: A vision for the road ahead
,” Science
362
(6412
), eaam9288
(2018
).29.
S.
Borówka
, U.
Pylypenko
, M.
Mazelanik
, and M.
Parniak
, “Continuous wideband microwave-to-optical converter based on room-temperature Rydberg atoms
,” Nat. Photonics
18
(1
), 32
–38
(2024
).30.
D.
Li
, Z.
Bai
, X.
Zuo
, Y.
Wu
, J.
Sheng
, and H.
Wu
, “Room temperature single-photon terahertz detection with thermal Rydberg atoms
,” Appl. Phys. Rev.
11
, 041420
(2024
).31.
K. C.
Cox
, D. H.
Meyer
, F. K.
Fatemi
, and P. D.
Kunz
, “Quantum-limited atomic receiver in the electrically small regime
,” Phys. Rev. Lett.
121
(11
), 110502
(2018
).32.
Y.
Du
, N.
Cong
, X.
Wei
, X.
Zhang
, W.
Luo
, J.
He
, and R.
Yang
, “Realization of multiband communications using different Rydberg final states
,” AIP Adv.
12
(6
), 065118
(2022
).33.
H.
Li
, J.
Hu
, J.
Bai
, M.
Shi
, Y.
Jiao
, J.
Zhao
, and S.
Jia
, “Rydberg atom-based AM receiver with a weak continuous frequency carrier
,” Opt. Express
30
(8
), 13522
–13529
(2022
).34.
S.
Berweger
, N.
Prajapati
, A. B.
Artusio-Glimpse
, A. P.
Rotunno
, R.
Brown
, C. L.
Holloway
, M. T.
Simons
, E.
Imhof
, S. R.
Jefferts
, B. N.
Kayim
, M. A.
Viray
, R.
Wyllie
, B. C.
Sawyer
, and T. G.
Walker
, “Rydberg-state engineering: Investigations of tuning schemes for continuous frequency sensing
,” Phys. Rev. Appl.
19
(4
), 044049
(2023
).35.
Y.
Jiao
, X.
Han
, J.
Fan
, G.
Raithel
, J.
Zhao
, and S.
Jia
, “Atom-based receiver for amplitude-modulated baseband signals in high-frequency radio communication
,” Appl. Phys. Express
12
(12
), 126002
(2019
).36.
D. H.
Meyer
, K. C.
Cox
, F. K.
Fatemi
, and P. D.
Kunz
, “Digital communication with Rydberg atoms and amplitude-modulated microwave fields
,” Appl. Phys. Lett.
112
(21
), 211108
(2018
).37.
D. A.
Anderson
, R. E.
Sapiro
, and G.
Raithel
, “An atomic receiver for AM and FM radio communication
,” IEEE Trans. Antennas Propag.
69
(5
), 2455
–2462
(2021
).38.
C. L.
Holloway
, M. T.
Simons
, J. A.
Gordon
, and D.
Novotny
, “Detecting and receiving phase-modulated signals with a Rydberg atom-based receiver
,” IEEE Antennas Wireless Propag.
18
(9
), 1853
–1857
(2019
).39.
Y.
Cai
, S.
Shi
, Y.
Zhou
, Y.
Li
, J.
Yu
, W.
Li
, and L.
Li
, “High-sensitivity Rydberg-atom-based phase-modulation receiver for frequency-division-multiplexing communication
,” Phys. Rev. Appl.
19
(4
), 044079
(2023
).40.
M.
Menchetti
, L. W.
Bussey
, D.
Gilks
, T.
Whitley
, C.
Constantinou
, and K.
Bongs
, “Digitally encoded RF to optical data transfer using excited Rb without the use of a local oscillator
,” J. Appl. Phys.
133
(1
), 014401
(2023
).41.
H.
Zou
, Z.
Song
, H.
Mu
, Z.
Feng
, J.
Qu
, and Q.
Wang
, “Atomic receiver by utilizing multiple radio-frequency coupling at Rydberg states of rubidium
,” Appl. Sci.
10
(4
), 1346
(2020
).42.
Y. Y.
Lin
, Z. Y.
She
, Z. W.
Chen
, X. Z.
Li
, C. X.
Zhang
, K. Y.
Liao
, X. D.
Zhang
, J. H.
Chen
, W.
Huang
, H.
Yan
, and S. L.
Zhu
, “Terahertz receiver based on room-temperature Rydberg-atoms
,” arXiv:2205.11021 (2023
).43.
D. H.
Meyer
, J. C.
Hill
, P. D.
Kunz
, and K. C.
Cox
, “Simultaneous multiband demodulation using a Rydberg atomic sensor
,” Phys. Rev. Appl.
19
(1
), 014025
(2023
).44.
J.
Han
, T.
Vogt
, C.
Gross
, D.
Jaksch
, M.
Kiffner
, and W.
Li
, “Coherent microwave-to-optical conversion via six-wave mixing in Rydberg atoms
,” Phys. Rev. Lett.
120
(9
), 093201
(2018
).45.
N. J.
Lambert
, A.
Rueda
, F.
Sedlmeir
, and H. G. L.
Schwefel
, “Coherent conversion between microwave and optical photons—An overview of physical implementations
,” Adv. Quantum Technol.
3
(1
), 1900077
(2020
).46.
N. R.
Laddha
and A. P.
Thakare
, “A review on serial communication by UART
,” Int. J. Adv. Res. Comput. Sci. Softw. Eng.
3
(1
), 366
–369
(2013
).47.
J. M.
Vanderau
, Delivered Audio Quality Measurements on Project 25 Land Mobile Radios
(Institute for Telecommunication Sciences
, 1998
).© 2025 Author(s). Published under an exclusive license by AIP Publishing.
2025
Author(s)
You do not currently have access to this content.
