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時間前後性の実験的検証に向けた量子光学実験の提案 ― 高速ビームスプリッター切替とHong–Ou–Mandel干渉を用いた検証 ―

恒久 千葉

Published Sep 17, 2026• 0 citations
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Abstract

タイトル (Title): Proposal for Quantum Optics Experiments Toward Experimental Verification of Temporal Bidirectionality: Verification Using High-Speed Beam Splitter Switching and Hong-Ou-Mandel Interference / 時間前後性の実験的検証に向けた量子光学実験の提案 - 高速ビームスプリッター切替とHong-Ou-Mandel干渉を用いた検証 - 説明 (Description): [English] This paper formulates the hypothesis of "temporal bidirectionality" in quantum phenomena and proposes an experimental scheme for its verification using quantum optics. Here, temporal bidirectionality refers to the possibility that temporal degrees of freedom corresponding to both before and after a process contribute to quantum state formation and interference. Specifically, we propose an experimental setup using Mach-Zehnder and Hong-Ou-Mandel (HOM) interferometers with high-speed optical path switching at frequency f. By introducing a characteristic time scale Δt, we establish a framework to compare standard quantum mechanical predictions against temporal bidirectionality models based on the frequency dependence of interference visibility V(f) and HOM dip parameters. The primary objective of this study is not to assert the existence of temporal bidirectionality a priori, but to translate a novel hypothesis on the structure of time into a falsifiable quantum optical test. [日本語] 本論文では、量子現象における「時間前後性 (temporal bidirectionality)」という仮説を定式化し、量子光学を用いた実験的検証方法を提案する。時間前後性とは、量子状態の形成や干渉過程において、通常の因果的記述に加え、時間の前後に対応する自由度が現象に寄与する可能性を指す。 具体的には、二光路干渉計やHong-Ou-Mandel (HOM) 干渉計において、ビームスプリッター等の光路選択機構を高速(切替周波数 f)に切り替え、干渉可視度 V(f) やHOM dipの変化を測定する手法を示す。標準量子力学の予測(VSQM)と時間前後性モデルの予測(VFB)を比較し、特徴的時間スケール Δt に対応する周波数領域において生じ得る異常な周波数依存性を検証する枠組みを提示する。 本研究の目的は時間前後性の存在を事前に主張することではなく、時間の構造に関する新しい仮説を反証可能な物理モデルとして評価・検証することにある。

DOI
10.5281/zenodo.22804821

Related papers

Proposal for Quantum Optics Experiments Toward Experimental Verification of Temporal Bidirectionality: Verification Using High-Speed Beam Splitter Switching and Hong-Ou-Mandel Interference / 時間前後性の実験的検証に向けた量子光学実験の提案 - 高速ビームスプリッター切替とHong-Ou-Mandel干渉を用いた検証 -

恒久 千葉

説明 (Description): [English] This paper formulates the hypothesis of "temporal bidirectionality" in quantum phenomena and proposes an experimental scheme for its verification using quantum optics. Here, temporal bidirectionality refers to the possibility that temporal degrees of freedom corresponding to both before and after a process contribute to quantum state formation and interference. Specifically, we propose an experimental setup using Mach-Zehnder and Hong-Ou-Mandel (HOM) interferometers with high-speed optical path switching at frequency f. By introducing a characteristic time scale Δt, we establish a framework to compare standard quantum mechanical predictions against temporal bidirectionality models based on the frequency dependence of interference visibility V(f) and HOM dip parameters. The primary objective of this study is not to assert the existence of temporal bidirectionality a priori, but to translate a novel hypothesis on the structure of time into a falsifiable quantum optical test. [日本語] 本論文では、量子現象における「時間前後性 (temporal bidirectionality)」という仮説を定式化し、量子光学を用いた実験的検証方法を提案する。時間前後性とは、量子状態の形成や干渉過程において、通常の因果的記述に加え、時間の前後に対応する自由度が現象に寄与する可能性を指す。 具体的には、二光路干渉計やHong-Ou-Mandel (HOM) 干渉計において、ビームスプリッター等の光路選択機構を高速(切替周波数 f)に切り替え、干渉可視度 V(f) やHOM dipの変化を測定する手法を示す。標準量子力学の予測(VSQM)と時間前後性モデルの予測(VFB)を比較し、特徴的時間スケール Δt に対応する周波数領域において生じ得る異常な周波数依存性を検証する枠組みを提示する。 本研究の目的は時間前後性の存在を事前に主張することではなく、時間の構造に関する新しい仮説を反証可能な物理モデルとして評価・検証することにある。

•Aug 24, 2026•0 citations

Proposal for Quantum Optics Experiments Toward Experimental Verification of Temporal Bidirectionality: Verification Using High-Speed Beam Splitter Switching and Hong-Ou-Mandel Interference / 時間前後性の実験的検証に向けた量子光学実験の提案 - 高速ビームスプリッター切替とHong-Ou-Mandel干渉を用いた検証 -

Tsunehisa Chiba

[English] This paper formulates the hypothesis of "temporal bidirectionality" in quantum phenomena and proposes an experimental scheme for its verification using quantum optics. Here, temporal bidirectionality refers to the possibility that temporal degrees of freedom corresponding to both before and after a process contribute to quantum state formation and interference. Specifically, we propose an experimental setup using Mach-Zehnder and Hong-Ou-Mandel (HOM) interferometers with high-speed optical path switching at frequency f. By introducing a characteristic time scale Δt, we establish a framework to compare standard quantum mechanical predictions against temporal bidirectionality models based on the frequency dependence of interference visibility V(f) and HOM dip parameters. The primary objective of this study is not to assert the existence of temporal bidirectionality a priori, but to translate a novel hypothesis on the structure of time into a falsifiable quantum optical test. [日本語] 本論文では、量子現象における「時間前後性 (temporal bidirectionality)」という仮説を定式化し、量子光学を用いた実験的検証方法を提案する。時間前後性とは、量子状態の形成や干渉過程において、通常の因果的記述に加え、時間の前後に対応する自由度が現象に寄与する可能性を指す。 具体的には、二光路干渉計やHong-Ou-Mandel (HOM) 干渉計において、ビームスプリッター等の光路選択機構を高速(切替周波数 f)に切り替え、干渉可視度 V(f) やHOM dipの変化を測定する手法を示す。標準量子力学の予測(VSQM)と時間前後性モデルの予測(VFB)を比較し、特徴的時間スケール Δt に対応する周波数領域において生じ得る異常な周波数依存性を検証する枠組みを提示する。 本研究の目的は時間前後性の存在を事前に主張することではなく、時間の構造に関する新しい仮説を反証可能な物理モデルとして評価・検証することにある。

•Aug 28, 2026•0 citations

《量子力学的时间闭环几何基础(The Temporal Loop Geometric Foundation of Quantum Mechanics)》

黄啸峰

摘要:量子力学自诞生以来,其数学框架经受了一切实验检验,但物理图像始终缺乏直观的几何理解。本文不从外部引入新假设,而是从量子力学自身的数学结构中,揭示一个被长期忽视的几何本体——时间闭环。本文正式提出时序法则,将时间闭环的时序状态分为五种:闭环收缩为点时的时序完全重叠(双向时间平衡态,χ=0),闭环极小时的时序趋于重叠(相干态),闭环正常时的经典时序(退相干态),反向闭环的时序颠倒(解构态),以及闭环极大时的时序孤立(绝对零度)。两种极限免疫策略——时序趋于重叠下的极速内循环,以及时序孤立下的刚性基态——各自提供对外部时间干扰的保护。相干态是时序趋于重叠的直接表现;退相干是量子系统与宏观仪器耦合时,仪器的宏观引力场通过引力层级拖拽将量子粒子的时间闭环周长拉长,使其从时序趋于重叠回归至经典时序的结果。光速是时序趋于重叠的临界节律——光子无质量,其时序状态被锁定在完全重叠态的临界面上,趋于重叠而永不重叠,光速不变原理在此获得了几何根源。在这一总纲下,时间闭环的S¹几何为双缝干涉、量子隧穿、纠缠和延迟选择实验提供了统一的定量解释。全部论证未引入额外假设,时间闭环的几何根源是手征维度。 Abstract: Since its inception, the mathematical framework of quantum mechanics has withstood all experimental tests, yet its physical picture has persistently lacked an intuitive geometric understanding. Without introducing external assumptions, this paper reveals, from within the mathematical structure of quantum mechanics itself, a long-neglected geometric entity: the temporal loop. This paper formally proposes the Temporal Principle, which classifies the temporal states of the temporal loop into five types: complete temporal overlap when the loop contracts to a point (bidirectional time equilibrium, χ=0), temporal near-overlap when the loop is extremely small (coherent state), classical temporality when the loop is normal (decoherent state), temporal inversion when the loop is reverse (deconstructed state) , and temporal isolation when the loop is extremely large (absolute zero). Two limit immunity strategies—ultra-rapid internal cycling under temporal near-overlap, and rigid ground-state protection under temporal isolation—each provide protection against external temporal disturbances. Coherence is the direct manifestation of temporal near-overlap; decoherence occurs when a quantum system couples with a macroscopic apparatus, whose macroscopic gravitational field stretches the quantum particle's temporal loop circumference via gravitational hierarchy drag, causing it to return from temporal near-overlap to classical temporality. The speed of light is the critical rhythm of temporal near-overlap—photons, being massless, have their temporal state locked on the critical surface of the complete overlap state, near-overlapping yet never overlapping,The principle of the constancy of the speed of light finds its geometric origin here. Under this overarching principle, the S¹ geometry of the temporal loop provides a unified quantitative explanation for double-slit interference, quantum tunneling, entanglement, and delayed-choice experiments. The entire argument introduces no additional hypotheses; the geometric origin of the temporal loop is the chiral dimension.

•Jun 19, 2026•0 citations

Which-path problem for one and two particles with two degrees of freedom and a relation between transverse spatial structure and group velocity of light

Gergely Ferenczi

Quantum mechanics, optics and indeed any wave theory exhibits the phenomenon of interference. In this thesis we present two problems investigating interference due to indistinguishable alternatives and a mostly unrelated investigation into the free space propagation speed of light pulses in particular spatial modes. In chapter 1 we introduce the basic properties of the electromagnetic field needed for the subsequent chapters. In chapter 2 we review the properties of interference using the beam splitter and the Mach-Zehnder interferometer. In particular we review what happens when one of the paths of the interferometer is marked in some way so that the particle having traversed it contains information as to which path it went down (to be followed up in chapter 3) and we review Hong-Ou-Mandel interference at a beam splitter (to be followed up in chapter 5). In chapter 3 we present the first of the interference problems. This consists of a nested Mach-Zehnder interferometer in which each of the free space propagation segments are weakly marked by mirrors vibrating at different frequencies [1]. The original experiment drew the conclusions that the photons followed disconnected paths. We partition the description of the light in the interferometer according to the number of paths it contains which-way information about and reinterpret the results reported in [1] in terms of the interference of paths spatially connected from source to detector. In chapter 4 we briefly review optical angular momentum, entanglement and spontaneous parametric down conversion. These concepts feed into chapter 5 in which we present the second of the interference problems namely Hong-Ou-Mandel interference with particles possessing two degrees of freedom. We analyse the problem in terms of exchange symmetry for both boson and fermion pairs and show that the particle statistics at a beam splitter can be controlled for suitably chosen states. We propose an experimental test of these ideas using orbital angular momentum entangled photons. In chapter 6 we look at the effect that the transverse spatial structure of the mode that a pulse of light is excited in has on its group velocity. We show that the resulting group velocity is slower than the speed of light in vacuum for plane waves and that this reduction in the group velocity is related to the spread in the wave vectors required to create the transverse spatial structure. We present experimental results of the measurement of this slowing down using Hong-Ou-Mandel interference.

•Jan 1, 2016•0 citations

Frequency entanglement characterization of short-pulse pumped SPDC biphoton source with a Mach-Zehnder interferometer

Yiwei Zhai, Ruifang Dong, Baihong Li +5 more

Abstract Frequency entangled biphoton sources have played an important role in quantum information. There are two key characteristics which determine the extent of their applications: the spectral indistinguishability and the degree of frequency entanglement. Previously, the spectral indistinguishability of the biphoton state is measured by the Hong–Ou–Mandel (HOM) interference visibility, whereas the degree of frequency entanglement is normally characterized with independent spectral measurements. However, these two quantum features have not been successfully measured with a single experimental setup. In this paper, we deduce the temporal distribution of a short-pulse pumped type-II spontaneous parametric down converted (SPDC) biphoton source and its relevant temporal entanglement parameter R t for operationally quantifying the degree of frequency entanglement. Furthermore, we theoretically and experimentally demonstrate, due to the inherent group delay, the difference between the signal and idler photons at the exit of the type-II nonlinear crystal, resulting in a HOM-shape dip at both sides of the center fringed envelope of the MZ interferometric coincidence diagram. By measuring the HOM-shape dip depth, the separation between the two sideband dips as well as the MZ fringed envelope width, both the spectral indistinguishability and the temporal entanglement parameter can thus be simultaneously quantified. This implementation provides us a unified and convenient method to characterize the frequency entanglement of the short-pulse pumped biphotons.

Journal of Physics B Atomic Molecular and Optical Physics•Jan 18, 2017•3 citations

カーパラメトリック発振器の結合系における量子アニーリングの断熱性の測定法の提案

Harunobu HIRATUKA

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•Jul 1, 2026•0 citations
タイトル (Title): Proposal for Quantum Optics Experiments Toward Experimental Verification of Temporal Bidirectionality: Verification Using High-Speed Beam Splitter Switching and Hong-Ou-Mandel Interference / 時間前後性の実験的検証に向けた量子光学実験の提案 - 高速ビームスプリッター切替とHong-Ou-Mandel干渉を用いた検証 - 説明 (Description): [English] This paper formulates the hypothesis of "temporal bidirectionality" in quantum phenomena and proposes an experimental scheme for its verification using quantum optics. Here, temporal bidirectionality refers to the possibility that temporal degrees of freedom corresponding to both before and after a process contribute to quantum state formation and interference. Specifically, we propose an experimental setup using Mach-Zehnder and Hong-Ou-Mandel (HOM) interferometers with high-speed optical path switching at frequency f. By introducing a characteristic time scale Δt, we establish a framework to compare standard quantum mechanical predictions against temporal bidirectionality models based on the frequency dependence of interference visibility V(f) and HOM dip parameters. The primary objective of this study is not to assert the existence of temporal bidirectionality a priori, but to translate a novel hypothesis on the structure of time into a falsifiable quantum optical test. [日本語] 本論文では、量子現象における「時間前後性 (temporal bidirectionality)」という仮説を定式化し、量子光学を用いた実験的検証方法を提案する。時間前後性とは、量子状態の形成や干渉過程において、通常の因果的記述に加え、時間の前後に対応する自由度が現象に寄与する可能性を指す。 具体的には、二光路干渉計やHong-Ou-Mandel (HOM) 干渉計において、ビームスプリッター等の光路選択機構を高速(切替周波数 f)に切り替え、干渉可視度 V(f) やHOM dipの変化を測定する手法を示す。標準量子力学の予測(VSQM)と時間前後性モデルの予測(VFB)を比較し、特徴的時間スケール Δt に対応する周波数領域において生じ得る異常な周波数依存性を検証する枠組みを提示する。 本研究の目的は時間前後性の存在を事前に主張することではなく、時間の構造に関する新しい仮説を反証可能な物理モデルとして評価・検証することにある。
説明 (Description): [English] This paper formulates the hypothesis of "temporal bidirectionality" in quantum phenomena and proposes an experimental scheme for its verification using quantum optics. Here, temporal bidirectionality refers to the possibility that temporal degrees of freedom corresponding to both before and after a process contribute to quantum state formation and interference. Specifically, we propose an experimental setup using Mach-Zehnder and Hong-Ou-Mandel (HOM) interferometers with high-speed optical path switching at frequency f. By introducing a characteristic time scale Δt, we establish a framework to compare standard quantum mechanical predictions against temporal bidirectionality models based on the frequency dependence of interference visibility V(f) and HOM dip parameters. The primary objective of this study is not to assert the existence of temporal bidirectionality a priori, but to translate a novel hypothesis on the structure of time into a falsifiable quantum optical test. [日本語] 本論文では、量子現象における「時間前後性 (temporal bidirectionality)」という仮説を定式化し、量子光学を用いた実験的検証方法を提案する。時間前後性とは、量子状態の形成や干渉過程において、通常の因果的記述に加え、時間の前後に対応する自由度が現象に寄与する可能性を指す。 具体的には、二光路干渉計やHong-Ou-Mandel (HOM) 干渉計において、ビームスプリッター等の光路選択機構を高速(切替周波数 f)に切り替え、干渉可視度 V(f) やHOM dipの変化を測定する手法を示す。標準量子力学の予測(VSQM)と時間前後性モデルの予測(VFB)を比較し、特徴的時間スケール Δt に対応する周波数領域において生じ得る異常な周波数依存性を検証する枠組みを提示する。 本研究の目的は時間前後性の存在を事前に主張することではなく、時間の構造に関する新しい仮説を反証可能な物理モデルとして評価・検証することにある。
[English] This paper formulates the hypothesis of "temporal bidirectionality" in quantum phenomena and proposes an experimental scheme for its verification using quantum optics. Here, temporal bidirectionality refers to the possibility that temporal degrees of freedom corresponding to both before and after a process contribute to quantum state formation and interference. Specifically, we propose an experimental setup using Mach-Zehnder and Hong-Ou-Mandel (HOM) interferometers with high-speed optical path switching at frequency f. By introducing a characteristic time scale Δt, we establish a framework to compare standard quantum mechanical predictions against temporal bidirectionality models based on the frequency dependence of interference visibility V(f) and HOM dip parameters. The primary objective of this study is not to assert the existence of temporal bidirectionality a priori, but to translate a novel hypothesis on the structure of time into a falsifiable quantum optical test. [日本語] 本論文では、量子現象における「時間前後性 (temporal bidirectionality)」という仮説を定式化し、量子光学を用いた実験的検証方法を提案する。時間前後性とは、量子状態の形成や干渉過程において、通常の因果的記述に加え、時間の前後に対応する自由度が現象に寄与する可能性を指す。 具体的には、二光路干渉計やHong-Ou-Mandel (HOM) 干渉計において、ビームスプリッター等の光路選択機構を高速(切替周波数 f)に切り替え、干渉可視度 V(f) やHOM dipの変化を測定する手法を示す。標準量子力学の予測(VSQM)と時間前後性モデルの予測(VFB)を比較し、特徴的時間スケール Δt に対応する周波数領域において生じ得る異常な周波数依存性を検証する枠組みを提示する。 本研究の目的は時間前後性の存在を事前に主張することではなく、時間の構造に関する新しい仮説を反証可能な物理モデルとして評価・検証することにある。
摘要:量子力学自诞生以来,其数学框架经受了一切实验检验,但物理图像始终缺乏直观的几何理解。本文不从外部引入新假设,而是从量子力学自身的数学结构中,揭示一个被长期忽视的几何本体——时间闭环。本文正式提出时序法则,将时间闭环的时序状态分为五种:闭环收缩为点时的时序完全重叠(双向时间平衡态,χ=0),闭环极小时的时序趋于重叠(相干态),闭环正常时的经典时序(退相干态),反向闭环的时序颠倒(解构态),以及闭环极大时的时序孤立(绝对零度)。两种极限免疫策略——时序趋于重叠下的极速内循环,以及时序孤立下的刚性基态——各自提供对外部时间干扰的保护。相干态是时序趋于重叠的直接表现;退相干是量子系统与宏观仪器耦合时,仪器的宏观引力场通过引力层级拖拽将量子粒子的时间闭环周长拉长,使其从时序趋于重叠回归至经典时序的结果。光速是时序趋于重叠的临界节律——光子无质量,其时序状态被锁定在完全重叠态的临界面上,趋于重叠而永不重叠,光速不变原理在此获得了几何根源。在这一总纲下,时间闭环的S¹几何为双缝干涉、量子隧穿、纠缠和延迟选择实验提供了统一的定量解释。全部论证未引入额外假设,时间闭环的几何根源是手征维度。 Abstract: Since its inception, the mathematical framework of quantum mechanics has withstood all experimental tests, yet its physical picture has persistently lacked an intuitive geometric understanding. Without introducing external assumptions, this paper reveals, from within the mathematical structure of quantum mechanics itself, a long-neglected geometric entity: the temporal loop. This paper formally proposes the Temporal Principle, which classifies the temporal states of the temporal loop into five types: complete temporal overlap when the loop contracts to a point (bidirectional time equilibrium, χ=0), temporal near-overlap when the loop is extremely small (coherent state), classical temporality when the loop is normal (decoherent state), temporal inversion when the loop is reverse (deconstructed state) , and temporal isolation when the loop is extremely large (absolute zero). Two limit immunity strategies—ultra-rapid internal cycling under temporal near-overlap, and rigid ground-state protection under temporal isolation—each provide protection against external temporal disturbances. Coherence is the direct manifestation of temporal near-overlap; decoherence occurs when a quantum system couples with a macroscopic apparatus, whose macroscopic gravitational field stretches the quantum particle's temporal loop circumference via gravitational hierarchy drag, causing it to return from temporal near-overlap to classical temporality. The speed of light is the critical rhythm of temporal near-overlap—photons, being massless, have their temporal state locked on the critical surface of the complete overlap state, near-overlapping yet never overlapping,The principle of the constancy of the speed of light finds its geometric origin here. Under this overarching principle, the S¹ geometry of the temporal loop provides a unified quantitative explanation for double-slit interference, quantum tunneling, entanglement, and delayed-choice experiments. The entire argument introduces no additional hypotheses; the geometric origin of the temporal loop is the chiral dimension.
Quantum mechanics, optics and indeed any wave theory exhibits the phenomenon of interference. In this thesis we present two problems investigating interference due to indistinguishable alternatives and a mostly unrelated investigation into the free space propagation speed of light pulses in particular spatial modes. In chapter 1 we introduce the basic properties of the electromagnetic field needed for the subsequent chapters. In chapter 2 we review the properties of interference using the beam splitter and the Mach-Zehnder interferometer. In particular we review what happens when one of the paths of the interferometer is marked in some way so that the particle having traversed it contains information as to which path it went down (to be followed up in chapter 3) and we review Hong-Ou-Mandel interference at a beam splitter (to be followed up in chapter 5). In chapter 3 we present the first of the interference problems. This consists of a nested Mach-Zehnder interferometer in which each of the free space propagation segments are weakly marked by mirrors vibrating at different frequencies [1]. The original experiment drew the conclusions that the photons followed disconnected paths. We partition the description of the light in the interferometer according to the number of paths it contains which-way information about and reinterpret the results reported in [1] in terms of the interference of paths spatially connected from source to detector. In chapter 4 we briefly review optical angular momentum, entanglement and spontaneous parametric down conversion. These concepts feed into chapter 5 in which we present the second of the interference problems namely Hong-Ou-Mandel interference with particles possessing two degrees of freedom. We analyse the problem in terms of exchange symmetry for both boson and fermion pairs and show that the particle statistics at a beam splitter can be controlled for suitably chosen states. We propose an experimental test of these ideas using orbital angular momentum entangled photons. In chapter 6 we look at the effect that the transverse spatial structure of the mode that a pulse of light is excited in has on its group velocity. We show that the resulting group velocity is slower than the speed of light in vacuum for plane waves and that this reduction in the group velocity is related to the spread in the wave vectors required to create the transverse spatial structure. We present experimental results of the measurement of this slowing down using Hong-Ou-Mandel interference.
Abstract Frequency entangled biphoton sources have played an important role in quantum information. There are two key characteristics which determine the extent of their applications: the spectral indistinguishability and the degree of frequency entanglement. Previously, the spectral indistinguishability of the biphoton state is measured by the Hong–Ou–Mandel (HOM) interference visibility, whereas the degree of frequency entanglement is normally characterized with independent spectral measurements. However, these two quantum features have not been successfully measured with a single experimental setup. In this paper, we deduce the temporal distribution of a short-pulse pumped type-II spontaneous parametric down converted (SPDC) biphoton source and its relevant temporal entanglement parameter R t for operationally quantifying the degree of frequency entanglement. Furthermore, we theoretically and experimentally demonstrate, due to the inherent group delay, the difference between the signal and idler photons at the exit of the type-II nonlinear crystal, resulting in a HOM-shape dip at both sides of the center fringed envelope of the MZ interferometric coincidence diagram. By measuring the HOM-shape dip depth, the separation between the two sideband dips as well as the MZ fringed envelope width, both the spectral indistinguishability and the temporal entanglement parameter can thus be simultaneously quantified. This implementation provides us a unified and convenient method to characterize the frequency entanglement of the short-pulse pumped biphotons.