We demonstrate that beam–beam interference can significantly enhance the efficiency of multi-beam traveling-wave devices. Our theoretical analysis explains that a positive coupling of the space-charge field enhances the beam–wave interaction, resulting in increased efficiency in multi-beam devices with beam–beam interference. We validate this mechanism by performing particle-in-cell simulations on 670 GHz grid-loaded rectangular waveguide backward-wave oscillators. Both the multi-beam and single-beam devices exhibit the same dispersion of operating modes and operate under identical conditions. The simulation results indicate that the efficiency of the multi-beam device is up to 1.58 times higher than that of the single-beam device. Additionally, simulations are performed on the same structure at 340 and 1030 GHz, demonstrating efficiency improvements that support the proposed mechanism. These findings present a novel approach for increasing the efficiency of traveling-wave devices.

1.
J.
Federici
and
L.
Moeller
, “
Review of terahertz and subterahertz wireless communications
,”
J. Appl. Phys.
107
(
11
),
111101
(
2010
).
2.
H.-J.
Song
and
T.
Nagatsuma
, “
Present and future of terahertz communications
,”
IEEE Trans. Terahertz Sci. Technol.
1
(
1
),
256
263
(
2011
).
3.
A. A.
Danylov
,
T. M.
Goyette
,
J.
Waldman
,
M. J.
Coulombe
,
A. J.
Gatesman
,
R. H.
Giles
,
X.
Qian
,
N.
Chandrayan
,
S.
Vangala
,
K.
Termkoa
,
W. D.
Goodhue
, and
W. E.
Nixon
, “
Terahertz inverse synthetic aperture radar (ISAR) imaging with a quantum cascade laser transmitter
,”
Opt. Express
18
(
15
),
16264
16272
(
2010
).
4.
P.
Siegel
, “
Terahertz technology in biology and medicine
,” in
Proceedings of the IEEE MTT-S International Microwave Symposium Digest
(
IEEE
,
2004
), Vol.
3
, pp.
1575
1578
.
5.
U. U.
Graf
,
C. E.
Honingh
,
K.
Jacobs
, and
J.
Stutzki
, “
Terahertz heterodyne array receivers for astronomy
,”
J. Infrared Millimeter Terahertz Waves
36
(
10
),
896
921
(
2015
).
6.
J. B.
Baxter
and
G. W.
Guglietta
, “
Terahertz spectroscopy
,”
Anal. Chem.
83
(
12
),
4342
4368
(
2011
).
7.
P. H.
Siegel
, “
Terahertz technology
,”
IEEE Trans. Microwave Theory Tech.
50
(
3
),
910
928
(
2002
).
8.
H. J.
Kim
,
E. A.
Nanni
,
M. A.
Shapiro
,
J. R.
Sirigiri
,
P. P.
Woskov
, and
R. J.
Temkin
, “
Amplification of picosecond pulses in a 140-GHz gyrotron-traveling wave tube
,”
Phys. Rev. Lett.
105
,
135101
(
2010
).
9.
B. A.
Knyazev
,
G. N.
Kulipanov
, and
N. A.
Vinokurov
, “
Novosibirsk terahertz free electron laser: Instrumentation development and experimental achievements
,”
Meas. Sci. Technol.
21
(
5
),
054017
(
2010
).
10.
C.
Paoloni
,
D.
Gamzina
,
R.
Letizia
,
Y.
Zheng
, and
N. C.
Luhmann
, “
Millimeter wave traveling wave tubes for the 21st century
,”
J. Electromagn. Waves Appl.
35
(
5
),
567
603
(
2021
).
11.
J. H.
Booske
,
R. J.
Dobbs
,
C. D.
Joye
,
C. L.
Kory
,
G. R.
Neil
,
G.-S.
Park
,
J.
Park
, and
R. J.
Temkin
, “
Vacuum electronic high power terahertz sources
,”
IEEE Trans. Terahertz Sci. Technol.
1
(
1
),
54
75
(
2011
).
12.
B.
Levush
,
D. K.
Abe
,
J. P.
Calame
,
B. G.
Danly
,
K. T.
Nguyen
,
E. J.
Dutkowski
,
R. H.
Abrams
, and
R. K.
Parker
, “
Vacuum electronics: Status and trends
,”
IEEE Aerosp. Electron. Syst. Mag.
22
(
9
),
28
34
(
2007
).
13.
P.
Hu
,
W.
Lei
,
Y.
Jiang
,
Y.
Huang
,
R.
Song
,
H.
Chen
, and
Y.
Dong
, “
Demonstration of a watt-level traveling wave tube amplifier operating above 0.3 THz
,”
IEEE Electron Device Lett.
40
(
6
),
973
976
(
2019
).
14.
J. C.
Tucek
,
M. A.
Basten
,
D. A.
Gallagher
,
K. E.
Kreischer
,
R.
Lai
,
V.
Radisic
,
K.
Leong
, and
R.
Mihailovich
, “
A 100 mW, 0.670 THz power module
,” in
Proceedings of the IVEC
, April (
IEEE
,
2012
), pp.
31
32
.
15.
J. C.
Tucek
,
M. A.
Basten
,
D. A.
Gallagher
, and
K. E.
Kreischer
, “
Testing of a 0.850 THz vacuum electronic power amplifier
,” in
Proceedings of the IEEE 14th International Vacuum Electronics Conference (IVEC)
, May (
IEEE
,
2013
), pp.
1
2
.
16.
J. C.
Tucek
,
M. A.
Basten
,
D. A.
Gallagher
, and
K. E.
Kreischer
, “
0.850 THz vacuum electronic power amplifier
,” in
Proceedings of the IEEE International Vacuum Electronics Conference
, April (
IEEE
,
2014
), pp.
153
154
.
17.
J. C.
Tucek
,
M. A.
Basten
,
D. A.
Gallagher
, and
K. E.
Kreischer
, “
Operation of a compact 1.03 THz power amplifier
,” in
Proceedings of the IEEE International Vacuum Electronics Conference (IVEC)
, April (
IEEE
,
2016
), pp.
1
2
.
18.
O. V.
Makarova
,
R.
Divan
,
J.
Tucek
,
K.
Kreischer
,
P. T.
Amstutz
,
D. C.
Mancini
, and
C.-M.
Tang
, “
9.3: Fabrication of solid copper 220 GHz folded waveguide circuits by UV lithography
,” in
Proceedings of the IEEE International Vacuum Electronics Conference (IVEC)
, May (
IEEE
,
2010
), pp.
183
184
.
19.
M.
Basten
,
J.
Tucek
,
D.
Gallagher
,
K.
Kreischer
,
J.
Liu
,
L.
Ives
, and
H.
Manohara
, “A
multiple electron beam array for a 220 GHz amplifier
,” in
Proceedings of the IEEE International Vacuum Electronics Conference
, April (
IEEE
,
2009
), pp.
110
111
.
20.
K. E.
Kreischer
,
J. C.
Tucek
,
M. A.
Basten
, and
D. A.
Gallagher
, “
220 GHz power amplifier testing at Northrop Grumman
,” in
Proceedings of the IEEE 14th International Vacuum Electronics Conference (IVEC)
, May (
IEEE
,
2013
), pp.
1
2
.
21.
J. C.
Tucek
,
M. A.
Basten
,
D. A.
Gallagher
, and
K. E.
Kreischer
, “
220 GHz power amplifier development at Northrop Grumman
,” in
Proceedings of the IVEC
, April (
IEEE
,
2012
), pp.
553
554
.
22.
Y.
Gong
,
H.
Yin
,
L.
Yue
,
Z.
Lu
,
Y.
Wei
,
J.
Feng
,
Z.
Duan
, and
X.
Xu
, “
A 140-GHz two-beam overmoded folded-waveguide traveling-wave tube
,”
IEEE Trans. Plasma Sci.
39
(
3
),
847
851
(
2011
).
23.
C.
Ruan
,
M.
Zhang
,
J.
Dai
,
C.
Zhang
,
S.
Wang
,
X.
Yang
, and
J.
Feng
, “
W-band multiple beam staggered double-vane traveling wave tube with broad band and high output power
,”
IEEE Trans. Plasma Sci.
43
(
7
),
2132
2139
(
2015
).
24.
J. R.
Pierce
, “
Traveling-wave tubes
,”
Bell Syst. Tech. J.
29
(
2
),
189
250
(
1950
).
25.
J.
Rowe
, “
A large-signal analysis of the traveling-wave amplifier: Theory and general results
,”
IRE Trans. Electron Devices
3
(
1
),
39
56
(
1956
).
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