Temporal resolution and fidelity enhancement of arbitrary waveforms

Patent metadata

Field	Value
Publication number	US-11868025-B2
Application number	US-202017075953-A
Country	US
Kind code	B2
Filing date	Oct 21, 2020
Priority date	Oct 21, 2020
Publication date	Jan 9, 2024
Grant date	Jan 9, 2024

Abstract

Apparatuses comprising cascaded or series configurations of Mach-Zehnder electrooptic modulators, where the nonlinearities of the cascaded and series configurations of Mach-Zehnder electrooptic modulators increase signal bandwidth and boost signal fidelity in electronic digital to analog converters. The Mach-Zehnder electrooptic modulators are combined with photodiode detectors that are used to convert signals from the optical domain to the electrical domain.

First claim

We claim:

1. An apparatus, comprising:
Mach-Zehnder modulators (MZMs) numbered MZM #1 to MZM #n;
a waveform source for applying a first voltage waveform to a first optical arm of said MZM #1;
a laser source for producing laser light and configured to direct said laser light into the two arms of at least said MZM #1 to produce a first output optical signal;
means utilizing said first output optical signal and MZMs numbered MZM #2 to said MZM #n to produce a final output voltage waveform, wherein:
said means utilizing said first output optical signal and MZMs numbered MZM #2 to said MZM #n comprise said MZMs numbered MZM #2 to said MZM #n configured in a cascaded configuration with MZM #1, wherein said first voltage waveform is only applied to said first arm of said MZM #1 and wherein said first output optical signal is detected and amplified by a first amplified detector to produce a first amplified voltage waveform that is applied to an optical arm of said MZM #2; or wherein
said means utilizing said first output optical signal and MZMs numbered MZM #2 to said MZM #n comprise said MZMs numbered MZM #2 to said MZM #n configured in a series configuration with MZM #1, wherein said first voltage waveform is applied to an optical arm of all said MZMs; and
wherein, compared to said input voltage, said output voltage waveform comprises at least one of
(i) a shorter rise time,
(ii) a shorter fall time,
(iii) increased signal temporal resolution,
(iv) increased small signal dynamic range,
(v) increased vertical resolution for small signals,
(vi) increased vertical resolution for large signals,
(vii) reduced noise on small signals,
(viii) reduced noise on large signals and
(ix) increased bandwidth.

2. The apparatus of claim 1 , wherein each said MZM is biased at the null.

3. An apparatus, comprising: a first stage including:
a first laser light source for providing first laser light;
a first Mach-Zehnder modulator (MZM) comprising a first optical arm and a second optical arm, wherein said first MZM is configured to receive at least a first portion of said first laser light into said first optical arm and at least a second portion of said first laser light into said second optical arm;
a waveform source for applying an input voltage waveform to one of said first optical arm or said second optical arm, wherein said first portion of said first laser light and said second portion of said first laser light propagate through said first MZM and interfere one with the other to produce a first output optical signal; and
a first amplified detector configured to detect said first output optical signal and produce a first output voltage waveform; and
a second stage comprising:
a second laser light source for providing second laser light;
a second MZM comprising a third optical arm and a fourth optical arm, wherein said second MZM is configured to receive at least a first portion of said second laser light into said third optical arm and at least a second portion of said second laser light into said fourth optical arm;
said first amplified detector being configured for applying said first output voltage waveform to one of said third optical arm or said fourth optical arm, wherein said first portion of said second laser light and said second portion of said second laser light propagate through said second MZM and interfere one with the other to produce a second output optical signal; and
a second amplified detector configured to detect said second output optical signal and produce a second output voltage waveform.

4. The apparatus of claim 3 , wherein said second output voltage waveform, compared to said input voltage waveform, has an enhancement selected from the group consisting of
(i) a shorter rise time,
(ii) a shorter fall time,
(iii) increased signal temporal resolution,
(iv) increased small signal dynamic range,
(v) increased vertical resolution for small signals,
(vi) increased vertical resolution for large signals, (vii) reduced noise on small signals, (viii) reduced noise on large signals and (ix) increased bandwidth.

5. The apparatus of claim 3 , wherein said first source of laser light and said second source of laser light are a single laser that provides both said first laser light and said second laser light.

6. The apparatus of claim 3 , wherein said first MZM and said second MZM are biased at the null.

7. An apparatus, comprising:
a waveform source for providing an input voltage waveform;
a source of laser light for providing laser light;
a series of Mach-Zehnder modulators (MZMs), wherein each MZM of said series comprises two optical arms;
the waveform source being configured for applying said input voltage waveform to one arm of said each MZM, wherein a first MZM of said series of said MZMs is configured to receive said laser light into its two optical arms and produce an output optical signal that is directed into the two arms of a second MZM of said series of MZMs, wherein said each MZM of said plurality of MZMs is configured to receive the respective output optical signal produced by its immediately preceding MZM, wherein the last MZM of said series produces a final output optical signal; and
an amplified detector configured to receive said final output optical signal to produce an output voltage waveform.

8. The apparatus of claim 7 , wherein said output voltage waveform, compared to said input voltage waveform, has an enhancement selected from the group consisting of
(i) a shorter rise time,
(ii) a shorter fall time,
(iii) increased signal temporal resolution,
(iv) increased small signal dynamic range,
(v) increased vertical resolution for small signals,
(vi) increased vertical resolution for large signals,
(vii) reduced noise on small signals,
(viii) reduced noise on large signals and
(ix) increased bandwidth.

9. The apparatus of claim 7 , wherein each said MZM of said series of MZMs is biased at the null.

10. A method, comprising:
providing Mach-Zehnder modulators (MZMs) numbered MZM #1 to MZM #n;
applying a first voltage waveform to a first optical arm of said MZM #1;
directing laser light into the two arms of at least said MZM #1 to produce a first output optical signal; and
utilizing said first output optical signal and MZMs numbered MZM #2 to said MZM #n to produce a final output voltage waveform, wherein:
said utilizing said first output optical signal and MZMs numbered MZM #2 to said MZM #n comprise utilizing said MZMs numbered MZM #2 to said MZM #n configured in a cascaded configuration with MZM #1, wherein said first voltage waveform is only applied to said first arm of said MZM #1 and wherein said first output optical signal is detected and amplified by a first amplified detector to produce a first amplified voltage waveform that is applied to an optical arm of said MZM #2; or wherein
said utilizing said first output optical signal and MZMs numbered MZM #2 to said MZM #n comprise utilizing said MZMs numbered MZM #2 to said MZM #n configured in a series configuration with MZM #1, wherein said first voltage waveform is applied to an optical arm of all said MZMs; and
wherein, compared to said input voltage, said output voltage waveform comprises at least one of
(i) a shorter rise time,
(ii) a shorter fall time,
(iii) increased signal temporal resolution,
(iv) increased small signal dynamic range,
(v) increased vertical resolution for small signals,
(vi) increased vertical resolution for large signals,
(vii) reduced noise on small signals,
(viii) reduced noise on large signals and
(ix) increased bandwidth.

11. The method of claim 10 , further comprising biasing each said MZM biased at the null.

Assignees

• L Livermore Nat Security Llc

Inventors

• Muir Ryan D
• Hernandez Vincent J
• Buckley Brandon W
• Mittelberger Daniel E
• Heebner John E

Classifications

• G02F7/00 Primary

  Optical analogue/digital converters · CPC title

• G02F1/2255 Primary

  controlled by a high-frequency electromagnetic component in an electric waveguide structure · CPC title

• G02F1/2257

  the optical waveguides being made of semiconducting material · CPC title

• H04B10/556

  Digital modulation, e.g. differential phase shift keying [DPSK] or frequency shift keying [FSK] · CPC title

• G02F1/212

  Mach-Zehnder type · CPC title